Now we're talking! When I was 16 and working summers for the village, our "truck" was a red 88 S-10 with the iron duke 4 banger. It had an AM only radio and no power steering. We called it the "S-9". One guy decided he was gonna buff and wax it by hand. He gave up pretty quickly and we drove it the rest of the summer with one shiny fender...
When I was an electrician apprentice back in the early 90's we had a GMC Sonoma shop truck. Iron Duke, manual trans, and no power steering. I hated that f'n truck! lol!
Fantastic diagnostic ability, a old army retired teacher always pounded it in our head, what's changed and what could change , Eric reminds me of that teacher. I've got the largest respect for these guys, it's a dying breed , now days we have parts replacers ,not technicians. Hats off to u Eric.
Yea I was working GM Fremont building cars and trucks 75-80 then was laid off. Americans were buying more foreign cars than domestic back then. So I feel old also bro.
We used to beat on the side of the pcm on these. Most of the time it would die or start missing. Put a ton of computers on these with the replaceable prom.
You got the O2 sensor out without breaking the pipe & found a pcm for that relic! I'm impressed, thanks for sharing! Now if you'll excuse me I need an early lunch!
Eric that is the 3rd generation of GM ECM, Engine Control Module. The first had a non replaceable PROM, Programmable Read Only Memory. 2nd generation had the removable PROM. 3rd generation had a PROM & an EPROM, the EPROM, I believe was the limp home for fuel injection or throttle body injection. The hair dryer will not get the circuit board hot to make it cut out. We had a 82 T16, Mini Blazer with 2.8, 700R4, with 120K miles, at 13 months old! It was a mail lady’s outfit. The first one that I ran into, the 3rd one that Chevrolet Technical Assistance ran into. She never had trouble in the winter, started having issues on hot spring days. One time when Ken removed the ECM, it was hot enough that it singed the carpet. I wish that I would have had your scan tools, instead of the KenTool, GM base special tool, OTC is what the tech assist sent us to use. As you were going through, I was remembering the trouble that I was having trying to make tools that now you can buy. Hello from north east Montana. 10 miles from the Canadian border.
Oh, the memories! My first set of wheels in 1999 was a '88 S10. Four cylinder, 2.5L, EFI, 5-speed manual, 2wd. It had a driveway paint job that I would touch up on the fly with a rattle can I kept in the glove box, a piece of 1/2” plywood where the tail gate should have been, if I hit a big enough pothole I would have to pick the radio up off the floor and slide it back in the dash, and I could get the dash lights to come on by giving it a 'Who's the Boss' Tony Danza whack. One time it had sat in my parents' driveway for months while I was away and no one was driving it; all of a sudden I needed a vehicle so we dug it out of a snow bank (literally half buried), boosted it with some jumper cables and my mother's minivan, and I hopped in and drove it two hours to the city where I was living and working and kept driving it everyday for a couple years after that. All that in Nova Scotia Canada salted roads winters. They don't make them like that anymore. I really miss that truck.
@@shadetreec6013 Oh yeah, like when he hit the jukebox? My nickname in high school for a while was the Fonz (a phase with a leather jacket and hair gel). But I have a memory of Tony hitting the roof liner or dash or something in his blue Chevy van to get the radio or something to work. Maybe I'm remembering it wrong.
I’m sure others have said, but it’s surely a few leaking capacitors that have eaten the original PCM. Sadly junkyard units will likely be on the same trajectory. A refurb that’s been recapped and had any trace damage repaired may result in more reliability.
I'd also rip off that cover and first have a look at the capacitors. If they look fine I'd take off the pcb and search for bad solder joints. Back in the days I owned a BMW where the entertainment ssystem did such weird things after some time, at hot weather more than in cold weather. BMW's offer was to put in a new radio for more than 1500$. I thanked them for the offer, went home resoldered a few joints and it worked like a charm for the next years untill I sold that car. But for Mr. O. that wouldn't probably be an option because of warranty issues...on the other hand, as you mentioned, if there is a cap-problem this guy will eventually run into some similar issues in the feauture.
Wow, Had no idea you watch this channel too Adrian! But absolutely my guess, it's becoming a thing on these old cars. I've recapped a few Ford PCM's and did some trace repairs with success.
Wow, what a great ending, and what a break that Wilbert's had a PCM available. Also not too shabby that an O2 sensor was readily available. And Mr. O had a scan tool that could read this old OBD-I system, and the know-how to interpret the data, so a win-win-win. But I think in your shop in upstate NY, that Kansas song in the background was really "Rust In The Wind".
@@POOKIE5592 big difference between pulling codes and seeing live data pids,codes would have done nothing here it was the wonky live data voltages that pointed towards bad ecu,it wasnt even throwing codes otherwise he would had pointed that out in begining for direction to go
You guys are such salt of the earth people. I drove by your shop one Sunday back in the winter on my way to Cleveland from Great Bend, Pa just to see where all my knowledge was coming from. You have enlightened me more than you will ever know!
Wow! What were the odds of Wilberts having a 31 year old PCM that wasn't junk also. Great diagnosis! Brought back good memories of tooling around a golf course in a S 10. Still don't know how you functioned after lunch. That looked like food coma city.
Holy crap, a friend of mine had S-10 blazer that did this. As an electronics tech I was saying, pop the case and shoot it with freeze spray the whole time lol.
Us electronics techs and our freeze spray. Hey a can of that stuff helped me troubleshoot a lot of test equipment when when I was servicing that stuff!
That was awesome. Thank you for providing the intimate test details and clear explanations of what you are doing and why. I love your videos, and always look forward to the next one.
I’ve had sooo many of these, and similar from that generation. Bought my first dime in 85 I think it was. I learned so much from them! Helped me to eventually become a licensed mechanic.
I just finished working on a 1986 Corvette. Some of the same problems displayed that you found. The ECM's go bad due to bad internal grounds in the ECM. The other thing I have found on these model years is bad grounds. They test ok with a voltage drop but still have problems. GM is well known for crap grounds. They used to ground the ECM to the bolts in the thermostat housing. I have fixed tons of these with just taking apart the ground connections and cleaning them up. Great video man.
Glad to see this rig still on the road! great trucks, my sister had an 88 blazer with a 4.3, great power and great in the snow. Sadly it succumbed to the cancer of the northeast… rust.
For the newbies out there… for the ECM replacement, you want to match the “service number” like 1226069. That’s the ecm itself model or part number. Then the prom chip inside should follow the vehicle. It has specs like which engine, trans, tire size, fuel and timing maps - list goes on. So you could swap them around and it might run, but it might not be right! Speedo could be out, engine might run funny. Or you could have an auto trans where all of a sudden you have an upshift light come on! That’s always fun. :)
Not too many “ newbies” today get to have the fun of removing that caterpillar prom without bending ! How many pcm’s are replaced today compared to the late 80’s into late 90’s.. Next to NIL ! LOL
Must be a "vintage" tech like myself. I remember all the fun with those years. Custom PROMs that eliminated limiters or changed tire sizes or gear ratios, think I still have the software someplace.
Living right on that one! Got the OG O2 sensor out AND found a PCM locally. Impressive. 👍 I really wanted to hear it run after the fix with the air cleaner lid flipped. 😆
Man, this brings back lots of old memories. I think you should start working on antiques like these more often. I would also be curious to know the cost on how much the owner spent fixing the original parts vs switching to a Holley efi system.
There’s none left that aren’t rotting in a field. Few and far between even in states like CA. Not cool enough to save and restore like classic muscle but old enough to have all been driven into the ground and scrapped
My first vehicle was an ‘88 S-10 Tahoe with the 2.8 V6 my brother sold to us for cheap. It was a fantastic truck. Got passed around to several family members and had almost 300,000 miles by the time we parted with it. I miss that truck dearly and would buy another first Gen S-10 in a heartbeat if I find a clean one. Oh yeah, I also flipped the air cleaner lid back in the day!
I had a 87 Chevy G-30 van, 4x4 pathfinder conversion. Same vintage TB injection. It started acting all crazy above 30 mph or so. Bucking and spitting, popping, pinging etc. after changing the usual suspects I noticed the engine temp sensor had a white lump growing out of the brass body. (I guess that’s the California version of “the green crusties” . I changed the sensor and the nightmare turned back into a dream!. Sad to say I sold it after 35 years and 265,000 miles…..(I’m crying inside right now). Great seeing you keep the oldies on the road.
Hi Eric, when you shot the underside, and said SHE"S MINT, and yeah "she"s pretty clean", I laughed till I cried ! You and Wes are the best repair guys on youtube , thanks for these long vids by the way !
This is becoming like the "Food and Fix" channel. Briskit, onion rings, pickles...Every time I watch this channel it's a contest over what goes higher - my RPMs of my Cholesterol. Eric, you need to change your outro to "...if I can eat it, YOU can eat it! Thanks for salivating...".
All the ingredients of a great SMA video, Mrs O, kickass lunch, an off camera trip to junkyard, blow torch action and off course a happy outcome. Well-done Eric.
I put a Howell Conversion Kit in an '87 4.2 Wrangler. The kit is a late 80's early 90's GM throttle body system. It runs well by comparison to the AMC carburetor and crazy emissions system. It's also CARB compliant, love NY. Lastly I never thought I'd see the day I actually installed a CEL in a vehicle that didn't come with one. I'm 73 and I learn something everytime, I previously thought the various sensor outputs would simply go thru the ECM to the scan tool. I wouldn't have know to check voltage at the connector and compare to scan tool reading. Time to finish putting a new front spring in my '29 Model A pickup. Thank you
I haven't started watching yet but this is what I've been asking for. I have an 89 GMC S-15 with the 2.5L that I like to tinker on. So I'm kind of a geek about these trucks.
I've lost count of how many first and second gen S10/S15's I've owned.But they're rare a hens teeth as they say now.Good to see one still on the road after all these years!You and Mrs O are something else,Y'all could have a sitcom of your very own.
Man does this bring back memories. In 1986 I was living in Mass & I bought/ordered a new 1986 2wd S-10 Blazer with 2.8l V6 with 5 speed manual. It had the exact same hi idle issue - but mine idles at 1200+ some times 1500+. Did this from new. Sometimes if you red lined 1st gear smacked 2nd gear & then red lined it & then put in neutral it would be at 3000RPM and stayed there for a bit. man was I glad it was a manual could you image with an automatic it would have took off on you. I took it to 2 different Chevy dealers - but they could never duplicate that 3000 rpm issue. Nor did the fix the normal 1200+ idle. Mass had yearly inspection were I would get rubber stamped to pass. failure due to hi idle. Now had I bought it & lived in Ohio - GM would have had to buy the truck back on lemon law. So over the years trying to fix it, I replaced every sensor on the engine with no luck - I did new engine in 1996. Distributor, Holley TBI over the years. nothing fixed the issue - as it got older the idle increase to the point it was permanently above 1500 closer to 1800. Buy tweaking the TPS volts to low side I was able to get the idle back below 1500. I owned another 1986 GMC S-15 Jimmy V6 & 5 speed manual up to mid 1993 & it idle at 800 like it was supposed to. Only diff was it was 4wd. which the ECU does not control But I never swapped the ECU between them. I should have but didn't. Looking in the ECU data it said that AC was on. Um I didn't have AC, should that be off. So I think the truck was sensing AC was on so it increase the idle speed to compensate, which I believe was the 1200+ rpm idle I was seeing. So I still own this 400,000 miles later - same issue. But in the last 10 years I did find a 1986 S-10 V6 manual in a pull & pay, I got that ECU & still had the same issue. Check the data - yep AC was set on. Never did figure out the 3000 rpm after reline shifts though.
This was a great diagnostic video. The three (3) things that were most likely to cause the symptoms the vehicle was showing, alternator producing high voltage, a floating ground (causing a higher voltage on the ECM, like the alternator might), or a bad ECM. And, you checked/tested those pretty much in that order. This diagnostics is an almost perfect diagnostics. One that all should strive for. Great job. The only thing that prevented it from being a perfect diagnostics, was that, well --- We did not get to eat any of your wives home cooking. Great choreography as well. Thank you for making these videos. I know they take more work and considerably more of your time to do. They are greatly appreciated. Omegaman69
Watching the car videos is enough, but combined with Mrs O when she has the cooking in, that's heaven right there. Great diagnostic work, I always enjoy your videos, they're easy to follow and awesome to learn from
This video hit pretty close to home, I had a 92 S10 Blazer Tahoe edition that I just retired to Gary's U-Pull-It and Binghamton New York a year or so ago, I sure do miss that old girl. I had a very large tree branch come down on the front clip, had to replace the front clip which I think probably tweaked the frame a little because I couldn't keep a tire on the front passenger side to save my life but anyway as a result I started having more and more structural problems, the roof started leaking so needless to say when the transmission shit the bed I decided it was time she got retired. I love your videos and I love the effort you put into working on vehicles and helping people
Eric, I ABSOLUTEL love your videos. I wish I could find a super skilled mechanic like you iny little town here in Oklahoma. I LOVE how you ANALYZE problems and never load a parts cannon until you have verified the faulty component. I am kinda an old school mechanic and have learned so much about using scan tools to find issue by diligently watching your channel. Keep up the excellent videos and I will keep on watching. THANKS ERIC (and thanks to Mrs. O for always taking good care of you. Her lunches look awesome.. FreddyB Claremore oklahoma, (no rust belt)
Oologah, Oklahoma is not any better.... Countryside Diesel Repair just NW of us, is a super good shop, they will put it back to OEM condition, and they work on everything.... Fixed my 5.3L Vortec Suburban a few years ago, compressor shelled out, and they found the O2 harness eaten up by sharp teeth.... PVC valve was bad, intake manifold gasket was mostly gone... it now runs like brand spanking new
For those of us that don't look at diag screens everyday, this was an awesome video. The basics of getting the O2 sensor to work and then watch the PCM toggle between rich/lean to get the correct mixture was refreshing to watch with the vastly simplified data display. I know you were stepping back into the "bad old days" but I really enjoyed the simplicity!
I have worked on many of these (in the LLV ) for the post office(tho they had the iron duke.) The later ones with distributor less ignition have constant ignition module, and pickup failures ALL of them have pin fitment issues and the early ones have prom fitment issues BUT these trucks have 30-37 years of hard use and are still out delivering your mail every day
I thought all those old llv's were scheduled to be replaced a couple years ago? Was i wrong? Did something change? (maybe the unspecified virus of unknown imported origin messed with schedules?)
@@colestowing8695 Yeah, they're finally being replaced. Still probably going to be 5-6 years before they actually start taking LLVs off the streets, think they are going to return the leased Mercedes Metris minivans first
Once, I tried to get a job with the Post Office working on their mail trucks. I think the hands on test on an old mail truck is what busted me out of the job opportunity. I was surprised that the running gear for those things were 1980s S-10 dinosaurs. The guy administering the test wanted me to look up all of the torque values and do everything according to the S-10 Haynes automotive manual. At the time, I was working fleet maintenance on newer pick-up trucks and medium duty trucks. I remember looking at the shop manager and saying: this thing has a old distributor, like who uses these things nowadays?! Looking things up in an old paper back manual also threw me for a loop.
Thanks! Excellent work! I didn't realize that scan tool would provide so much data from a 1988 vehicle. Also, I wouldn't have thought you could swap the chips like that. Gives me something new to consider as I try to keep my fleet of antique steel running!
Yep, shed a tear for us Ford Techs. No serial data access like the GM guys got pre-1990 until EEC-5 which was 1998-99 in the market I worked in. Even then the PIDs were full of anomalies like HEGO voltages in the 2v range, ECT in degF vs CHT in degC, things like that to keep you on your toes😊
That was the cool guy terminology back then...ohh yeah duel exhaust, lift kit Micky Thompson's. But Is it chipped..? Ohhh man those were the days. I mis carburetors
Watching Mr .O has given me confidence to diag more complicated problems on my vehicles… only problem now is tool availability, i could do more if I had more!!! Thank you Mr.O sir!!!
Got to compliment you on your resolve mr O, there is a reason so many of those went to the crusher. As I watched you work on that I passed out twice and had one sezure. Horrible memories I thought I had buried. Thanks
definitely a cool diagnostic on an old rig. not many of those around nowadays, i havent seen a blazer/jimmy of that vintage here in Toronto for years. all rusted out and/or scrapped due to drive test emissions.
Yeah the old freezer fix, Been a while since I've seen that one. Remember an 85 S-blazer with this problem, the owner had a hose rigged from the AC duct to a box around the PCM to keep it cold! Good old OBD "high speed" interface... LOL
Own 2 S-10s, a '93 350 swapped daily and a '91 4.3L, but worked on several 2.8Ls, never had the pleasure of dealing with old candle stick O2 sensor but yeah fire is a MUST for removal, have several PCMs due to internal gremlin issues, hard to kill these trucks, looking at an '88 manual right now, Great Work Mr. O! Love your channel!
I was waiting on someone to mention the rubber hammer test. Had a late 80's GM that I could turn the AC on and off with a rap of the rubber hammer to the ECM.
I'm glad you were able to find that ECU. If you didn't have one, I have a spare ECU in the basement from a 1989 S10 Tahoe 4x4 auto pickup. Mine is for the 4.3L but the 2.8L proms would've worked on it. So I don't have to send it to you. :-) When you said you'd need to hunt one down in part II, I thought I'd give you a call and let you know I have one, but apparently your local parts yard is the best!
Dude, you have gotten so much better at doing videos, compared the "Dr. O" days. :-) But your videos are always very informative. Thank you for all you do. Great Channel.
Hi Eric and the lovely Mrs. O. I had this happen to my Mothers Cavalier, after a few hrs. of back probing I came up with confusion because everything kept changing. The original problem was it would be running fine then all of sudden would backfire through the throttle body and quit running. Then the tap test came to mind, had the ECM in hand the eng. running and knocked on it with my knuckle and it backfired and quit running. To make a short story shorter, I replaced the ECM and never had another problem. I have a 1991 S-10 pick-up with a 2.8 V-6 5spd. with 224K miles and have never had any problems except the electronic analog speedo goes crazy when its cold but works perfect all summer. I think the circuit board might be at fault but every time I try to check it works fine and so it goes. Great videos Eric and sat Hi to the lovely Mrs. O.
Instead of putting it in the freezer you could spray it with caned air (computer duster) that's a lot colder than your freezer. Just an option if you want to speed things up.
@@kdodds80 I guess in this case it was cheaper but he said he got lucky that he was even able to find one. I would at least try just to see. At least LOOK at it. It might have been just a solder joint.
@keith agreed. the freeze spray is only for thermal intermittents, which is almost always joints & traces that go bad with thermal cycling. bad caps don't start working again like this, and bad ic's are usu. either good or bad from the factory and stay that way.
Bringin' the heat! I have a 1970's Schwinn (bicycle) which I've mostly updated to modern components. However, the one-piece crank was still OEM. To get modern clip-in pedals to function with the old crank, special adapter pieces were needed. I installed the adapters a few years ago and the bike has seen a half dozen thousand miles of use since. Well, this season, I decided to replace the OEM one-piece crank with a sealed bearing 3-piece... I wanted to save those clip-in pedals, however, which required the removal of the adapters. The problem? The adapters will spin on for installation. But, there's no way to grip the part for removal. I had to disassemble the pedal down to its shaft, mount the thing (bearing surface) in a small set of V-block vise jaws, and apply heat... Without the heat, I would have had to crush the pedal shaft (bearing surface) in the vise so much, it would have damaged the machined rolling surface. Looking back, I wonder how I ever got anything done without a smoke wrench in the shop!
Oh, and speaking of, "Bringin' the heat," I was scanning Facebook Marketplace while listening to Eric. Someone has a pair of "Settling" tanks for sale. "Settlin'" is country-speak is for "acetylene." Made me giggle, it did!
GM around this timeframe was using a spray coating on the circuit boards to prevent corrosion that would actually shrink with heat cycles and over time pull on components and create lots of intermittent issues like this. I owned a couple Geo Storms from the same era with the same kinds of PCM problems. Just throwing that out there as another root cause possibility
yeah i was gonna say taiwan - even back than - could produce 100% reliable parts like the pcm. so, it is sad that G.M. still wanted to " get away " with something. took a long time for chrysler and G.M. to go bankrupt. In the end it was handshake deal under-the-table with the government to re-negotiate their pension obligations. in the 1960's we said " as G.M. goes, so goes the country. "
One thing I've always done is use a cutoff wheel and cut the O2 sensor off at hex nut. Then you can get a 6 point socket / impact driver etc. in there to remove it.
Those anti-foulers got.many cars to pass inspections in the day and replaced the spiders in the old S-10's too many times to count. Love that"Pick and Pull" saves again.
Appreciate the effort, Eric I have one too I have an 89 but mine runs pretty good 5 speed. Easy to work on thank you very much you're very much appreciated
I had a Cadillac of this vintage that had very similar symptoms. It turned out that the alternator ground was bad and it was under charging causing the computer to be unhappy.
If i remember correctly, the early 4.3s had the same wiring harness as the 2.8s. I think they literally just put in a different prom but everything else is the same. It wasnt until they went to port fuel injection that they actually updated their PCMs and harnesses and sensors etc, but i dont think the 2.8 ever got port fuel injection on the trucks.
Had that exact problem. Bought all the sensors that I could from a boneyard truck including the ECM. Changed them all and lastly the ECM. Bam! Nailed it. Mine was a '93 Chevy 1500 with a 350. Love your work!
Those old ECU’s capacitors start leaking over time. Even a working used ECU will suffer the same fate sooner than later. Recapping them before damage to the circuit board is a good idea if you plan on keeping a car that old.
Great video 90 GMC Safari van for 3 l solo problems and give me a direction hopping up all set to strange issues is an idea on how to track the problem thanks Eric
Great video 90 GMC Safari van for 3 l solo problems and give me a direction hopping up all set to strange issues is an idea on how to track the problem thanks Eric
It's because you are a Real Technician that I enjoy your Channel. Some garages just guess and replace. Once I find it impossible to get parts, I start to believe the vehicle is ready to get rid of, sadly.
I am a retired, lifetime GM dealership employee from Tech to Service and Parts Director....( a little background ). When our products had a widespread problem with drivability, they would come out with a bulletin, a widespread rattle problem, guess what?...Yup, another one page bulletin from the engineers. The point I am getting at is the fix is usually a sheet of paper with the "how to"......Here is the kicker, guys.... The drivability bulletin on the 2.8 in the late 80's was a 36 page book. A freaking BOOK.( I have one as a souvenir ). It was mostly 2.8 V6 engines in cars, but, it was always the 2.8. They never ran perfectly, like the 3.8 V6 did.........
84 - 86 Buick roadmaster had a recall on the proms....I got involved with that program for while back in 88.....working at a dealership in NJ..,..keep up the good work bud
My current daily driver, grocery getter, dog hauler is a 96 S10 Blazer. It’s got the big 4.3, no rust anywhere, 110k, and mine too has a fragrance, … wet dog! It was free and I love it!
@@forindooruseonly646 i disagree. I pretty much beat the average vehicle off the line here. I've an 86 2.8 with TBI. No work done. Automatic. Still OG engine with just over 200k miles, my DD. Now the manual version, they're dogs but that's a trans issue, not engine.
It amaze me, a simplicity to check all grounds and voltages into PCM, even the reference voltage circuit. It reminds me from other of yours valuable videos, a clean and very neat task to verify each in and out wire from a BCM module . At the end may be a variable contact from a peeled-piched cable to ground, my fat bet was in the reference voltage circuit. Thanks Mr. Erick O. Wish you good luck as always.
Got 1988 Ford Maverick 4.2 petrol or a Nissan Patrol rebagded, just replacing original alternator, parts ready but a public holiday for the Queens funeral here in Australia, I am in the Northern Territory and live like a hermit 135ks away from the spare parts place, what a hassel, I have charged up my tractor battery as the car battery has also died and hopefully I will be able to get to the spare parts tomorrow and back to where I live to replace it, luv the car, use 4wd nearly every day prospecting in country most people will never see. Have a good day, really enjoy your videos on my days stuck at home.
@@CubasAutomotive Same vintage as the old ford EEC-4 system. They had a bunch of electrolytic caps that get leaky. (Shago on his channel shows basic repairs and the damage leaky electrolytic caps cause.) Not saying wrong or right, but yes..older PCM's can and do use electrolytic's in some models.
@@Tedybear315 yes, some do use electrolytic capacitors. Agreed. Not in this case. I've done all sorts of board repairs too. TVs, PCs, ECMs, and other modules.
ABSOLUTELY LOVE THE INFORMATION ON HOW TO BACK PROBE THESE COMPUTERS AND THE TEST LIGHTS AND T-PINS TO BACK PROBE!!!!!! DUDE YOURE A BLESSING TO A YOUNG TECH LIKE ME!!! GOD BLESS FROM GEORGIA
These were great basic trucks... the V6's were decent power, and pretty reliable. and easy to work on. It's kind of amazing to me that it ran at all.. with that much corrupted or missing data/ feedback.. sometimes simple is better. Makes me want to go find one of these.. be a great basic practical truck.
I like that test with the "sniffer" to check for evap core leaks. The test tool has lights for leak checks which is great, and the oil injection tool looks like a big help.
Good to see you work on an old car. Problem sounds like mass air censer. I had the same problem with my 87 Camaro. Three dealers couldn't figure it out, and the manufacturer couldn't care less. Always nice to see Mrs. O, She does treat you well.
These used speed density programming, computer used the map sensor and tps reading to calculate fuel while in open loop. After it went into closed loop, it'd use the O2 sensor.
At 32:17 I was wondering if there was a heater hose under the dash near the computer. At 41:23 I was wondering if the internal regulator might be failing, but I'm an electrical engineer and that's not something that I would expect a normal automotive tech to dig into. -. Nice job with the O2. One thing I might have added to what you did, was to put some nickel anti-seize on the threads of the O2 bung. I found that it makes a big difference on parts that are hard to get out because they aren't replaced very often, when they are replaced the second time. If this truck had been typically rusty it wouldn't make a difference, but it looks like this owner may restore and preserve the truck for a long time.
Having moved to Texas from WNY 45 YRS ago... I have the brisket thing down. We don't have kaisers/wecks here. I make my own wings... but I do miss beef on wecks. :-( You make me sad, Eric! Haven't seen you in a few months. I guess the algorithm has come back around. Cheers, guys!
FYI: It is not unusual, in electronics troubleshooting, to use "spray cooler" to cool off components to see if they react to temperature. (any quick-drying spray which does not leave residue would work...perhaps brakleen?) My bet for this one is cracked solder-joint which just needed to be re-flowed.
It's almost definitely dried out capacitors and/or cracked solder joints around component leads and connector pins. I've repaired some old ECM/PCM modules before. Sometimes the capacitors also leak electrolyte onto the board and corrode the traces. Cooling down the board and gaining functionality indicates that it's not corroded, though. Freeze spray is great, but it also requires direct access to the PCB.
REALLY love this in depth dive into troubleshooting on some seriously wacky behavior. Incredibly thorough work as usual for Mr. O which results in yet another W
Now we're talking! When I was 16 and working summers for the village, our "truck" was a red 88 S-10 with the iron duke 4 banger. It had an AM only radio and no power steering. We called it the "S-9". One guy decided he was gonna buff and wax it by hand. He gave up pretty quickly and we drove it the rest of the summer with one shiny fender...
😂
When I was an electrician apprentice back in the early 90's we had a GMC Sonoma shop truck. Iron Duke, manual trans, and no power steering. I hated that f'n truck! lol!
Fender splendor :)
I had a "77 PONTIAC SUNBIRD with the 2.5 Iron Duke. Sold it for $100 @188k.
Wes, if your donkey powered internet is working good enough to watch SMA, you better give us a vid!
Fantastic diagnostic ability, a old army retired teacher always pounded it in our head, what's changed and what could change , Eric reminds me of that teacher. I've got the largest respect for these guys, it's a dying breed , now days we have parts replacers ,not technicians. Hats off to u Eric.
Now days people dont have a clue what they are doing. I see it the younger generation. Most of them cant do or know anything.
That o2 sensor extraction: oddly satisfying
Hearing you say, "before your time" makes me feel old. I remember working on these new. lol I'm so old, I should be in a home!
Your just a kid, The first car I worked on was a '49 chevy.
Yea I was working GM Fremont building cars and trucks 75-80 then was laid off. Americans were buying more foreign cars than domestic back then. So I feel old also bro.
I bought one of these trucks brand new, it didn't have the power to pull itself up the hill I lived on lol.
Vehcor no way, do not do the home thing. Count every day as a blessing and keep moving. God bless
We used to beat on the side of the pcm on these. Most of the time it would die or start missing. Put a ton of computers on these with the replaceable prom.
You got the O2 sensor out without breaking the pipe & found a pcm for that relic! I'm impressed, thanks for sharing! Now if you'll excuse me I need an early lunch!
I believe that deserves an extra helping of brisket
I have an O2 sensor to get out tomorrow. It's the first one I have ever personally done now that I'm thinking about it.
Wish me luck!
Did you go out and buy a lottery ticket that night?
@@kevinrenn9123 Roll it up my man!
Mmm lunch.
Eric that is the 3rd generation of GM ECM, Engine Control Module.
The first had a non replaceable PROM, Programmable Read Only Memory.
2nd generation had the removable PROM.
3rd generation had a PROM & an EPROM, the EPROM, I believe was the limp home for fuel injection or throttle body injection.
The hair dryer will not get the circuit board hot to make it cut out.
We had a 82 T16, Mini Blazer with 2.8, 700R4, with 120K miles, at 13 months old! It was a mail lady’s outfit. The first one that I ran into, the 3rd one that Chevrolet Technical Assistance ran into. She never had trouble in the winter, started having issues on hot spring days.
One time when Ken removed the ECM, it was hot enough that it singed the carpet.
I wish that I would have had your scan tools, instead of the KenTool, GM base special tool, OTC is what the tech assist sent us to use.
As you were going through, I was remembering the trouble that I was having trying to make tools that now you can buy.
Hello from north east Montana.
10 miles from the Canadian border.
Oh, the memories! My first set of wheels in 1999 was a '88 S10. Four cylinder, 2.5L, EFI, 5-speed manual, 2wd. It had a driveway paint job that I would touch up on the fly with a rattle can I kept in the glove box, a piece of 1/2” plywood where the tail gate should have been, if I hit a big enough pothole I would have to pick the radio up off the floor and slide it back in the dash, and I could get the dash lights to come on by giving it a 'Who's the Boss' Tony Danza whack. One time it had sat in my parents' driveway for months while I was away and no one was driving it; all of a sudden I needed a vehicle so we dug it out of a snow bank (literally half buried), boosted it with some jumper cables and my mother's minivan, and I hopped in and drove it two hours to the city where I was living and working and kept driving it everyday for a couple years after that. All that in Nova Scotia Canada salted roads winters. They don't make them like that anymore. I really miss that truck.
The dash whack is called a Fonzarelli, not a Tony Danza
I miss my 89 s10 blazer with a 4.3
@@shadetreec6013 Oh yeah, like when he hit the jukebox? My nickname in high school for a while was the Fonz (a phase with a leather jacket and hair gel). But I have a memory of Tony hitting the roof liner or dash or something in his blue Chevy van to get the radio or something to work. Maybe I'm remembering it wrong.
the most valuable thing in life are memories
@@shadetreec6013 "This bucket of bolts is never gonna get us past that blockade!!"
I’m sure others have said, but it’s surely a few leaking capacitors that have eaten the original PCM. Sadly junkyard units will likely be on the same trajectory. A refurb that’s been recapped and had any trace damage repaired may result in more reliability.
I'm thinking this truck would be a decent candidate for a cardrino or speedrino if it ends up with more problems with the computer.
I'd also rip off that cover and first have a look at the capacitors. If they look fine I'd take off the pcb and search for bad solder joints.
Back in the days I owned a BMW where the entertainment ssystem did such weird things after some time, at hot weather more than in cold weather. BMW's offer was to put in a new radio for more than 1500$. I thanked them for the offer, went home resoldered a few joints and it worked like a charm for the next years untill I sold that car.
But for Mr. O. that wouldn't probably be an option because of warranty issues...on the other hand, as you mentioned, if there is a cap-problem this guy will eventually run into some similar issues in the feauture.
Absolutely. If you can catch those electrolytics before the leak and kill the traces, its a pretty easy fix if you have some soldering skills.
Wow, Had no idea you watch this channel too Adrian! But absolutely my guess, it's becoming a thing on these old cars. I've recapped a few Ford PCM's and did some trace repairs with success.
@@dougkoudelka3089 I recapped an ECU once. I think I was holding my breath the entire time. The breath holding was used in place of soldering skills.
Wow, what a great ending, and what a break that Wilbert's had a PCM available. Also not too shabby that an O2 sensor was readily available. And Mr. O had a scan tool that could read this old OBD-I system, and the know-how to interpret the data, so a win-win-win. But I think in your shop in upstate NY, that Kansas song in the background was really "Rust In The Wind".
Great! Now I have that song with modified lyrics stuck in my head. All our cars are rust in the wind. 😎
Tom Lewis You can retrieve OBD-1 codes with a paperclip.
@@POOKIE5592 big difference between pulling codes and seeing live data pids,codes would have done nothing here it was the wonky live data voltages that pointed towards bad ecu,it wasnt even throwing codes otherwise he would had pointed that out in begining for direction to go
Spoilers!! I haven’t watched it yet! Lol.
PRetty sure this sucker was just heat cycling the board enough over the years it started fucking some through hole solder joints and probably fixable!
I didn't have much hope for this video when it started, but it turned into one of the best SMA vids in recent memory. Thank you.
You guys are such salt of the earth people. I drove by your shop one Sunday back in the winter on my way to Cleveland from Great Bend, Pa just to see where all my knowledge was coming from. You have enlightened me more than you will ever know!
I had a 85 celebrity and it same problem was the PCM bought a new one was 65 dollars and 20 yr ago .
The upside down air filter cover - vintage!
And that lunch with homemade potato salad, to die for.
And ya, we all love Mrs.O, and you too Eric
Memories of my '68 Impala SS ragtop, 327/300 HP. Only car ever to be pulled over for a LOUD CARBURETOR!
Wow what a stroke of luck finding that PCM, great fix Eric, and a thumps up for Mrs. O, the most valuable employee at the shop.
Don’t forget the kids and the cat. 😌 ❤️
Wow! What were the odds of Wilberts having a 31 year old PCM that wasn't junk also. Great diagnosis! Brought back good memories of tooling around a golf course in a S 10. Still don't know how you functioned after lunch. That looked like food coma city.
Holy crap, a friend of mine had S-10 blazer that did this.
As an electronics tech I was saying, pop the case and shoot it with freeze spray the whole time lol.
Us electronics techs and our freeze spray. Hey a can of that stuff helped me troubleshoot a lot of test equipment when when I was servicing that stuff!
Only when needed....
That was awesome. Thank you for providing the intimate test details and clear explanations of what you are doing and why. I love your videos, and always look forward to the next one.
I’ve had sooo many of these, and similar from that generation. Bought my first dime in 85 I think it was. I learned so much from them! Helped me to eventually become a licensed mechanic.
I just finished working on a 1986 Corvette. Some of the same problems displayed that you found. The ECM's go bad due to bad internal grounds in the ECM. The other thing I have found on these model years is bad grounds. They test ok with a voltage drop but still have problems. GM is well known for crap grounds. They used to ground the ECM to the bolts in the thermostat housing. I have fixed tons of these with just taking apart the ground connections and cleaning them up. Great video man.
Love all these OBD1 diags...A true test of a mechanics ability
Glad to see this rig still on the road! great trucks, my sister had an 88 blazer with a 4.3, great power and great in the snow. Sadly it succumbed to the cancer of the northeast… rust.
For the newbies out there… for the ECM replacement, you want to match the “service number” like 1226069. That’s the ecm itself model or part number. Then the prom chip inside should follow the vehicle. It has specs like which engine, trans, tire size, fuel and timing maps - list goes on. So you could swap them around and it might run, but it might not be right! Speedo could be out, engine might run funny. Or you could have an auto trans where all of a sudden you have an upshift light come on! That’s always fun. :)
Not too many “ newbies” today get to have the fun of removing that caterpillar prom without bending ! How many pcm’s are replaced today compared to the late 80’s into late 90’s.. Next to NIL ! LOL
Maybe would be a good idea, if your the customer, to put it on a prom reader and copy the data, so if the prom ever died, you'd have a back up.
Yeah as long as the ECM is the same part number, just need to switch the MEMCAL and you're good.
@@Discretesignals No backup, no mercy.😁
Must be a "vintage" tech like myself. I remember all the fun with those years. Custom PROMs that eliminated limiters or changed tire sizes or gear ratios, think I still have the software someplace.
This channel is the best. From relating the king pin bushing to the fout post lift bushings to the 88 S10
Issues.
Living right on that one! Got the OG O2 sensor out AND found a PCM locally. Impressive. 👍
I really wanted to hear it run after the fix with the air cleaner lid flipped. 😆
Man, this brings back lots of old memories. I think you should start working on antiques like these more often. I would also be curious to know the cost on how much the owner spent fixing the original parts vs switching to a Holley efi system.
There’s none left that aren’t rotting in a field. Few and far between even in states like CA. Not cool enough to save and restore like classic muscle but old enough to have all been driven into the ground and scrapped
My first vehicle was an ‘88 S-10 Tahoe with the 2.8 V6 my brother sold to us for cheap. It was a fantastic truck. Got passed around to several family members and had almost 300,000 miles by the time we parted with it. I miss that truck dearly and would buy another first Gen S-10 in a heartbeat if I find a clean one. Oh yeah, I also flipped the air cleaner lid back in the day!
Walking through SMA archives. I love seeing old vehicles like this get attention. Back in the day, this computer communication was beyond amazing!
Yes, it looks like a cold solder joint.
Mr O send the malfunctioning PCM to our friend Ivan he will take care of it. Nice vid.
For sure…he will change his mind a few times,,,,but he “allways gets his man!” LOL
I had a 87 Chevy G-30 van, 4x4 pathfinder conversion. Same vintage TB injection. It started acting all crazy above 30 mph or so. Bucking and spitting, popping, pinging etc. after changing the usual suspects I noticed the engine temp sensor had a white lump growing out of the brass body. (I guess that’s the California version of “the green crusties” . I changed the sensor and the nightmare turned back into a dream!. Sad to say I sold it after 35 years and 265,000 miles…..(I’m crying inside right now). Great seeing you keep the oldies on the road.
Hi Eric, when you shot the underside, and said SHE"S MINT, and yeah "she"s pretty clean", I laughed till I cried ! You and Wes are the best repair guys on youtube , thanks for these long vids by the way !
This is becoming like the "Food and Fix" channel. Briskit, onion rings, pickles...Every time I watch this channel it's a contest over what goes higher - my RPMs of my Cholesterol. Eric, you need to change your outro to "...if I can eat it, YOU can eat it! Thanks for salivating...".
Love hugs and prayers to you Mrs.O and Family, you two are an awesome and good people, what the world needs!
I just ate and I’m hungry looking at that food. Eric, you Sir are a spoiled man! Somebody should be. 👌🏻
All the ingredients of a great SMA video, Mrs O, kickass lunch, an off camera trip to junkyard, blow torch action and off course a happy outcome.
Well-done Eric.
you forgot the Cat and Fly...
Just missing the noon siren and a spray of Brakleen!
CHEVY THUNDER!
I put a Howell Conversion Kit in an '87 4.2 Wrangler. The kit is a late 80's early 90's GM throttle body system. It runs well by comparison to the AMC carburetor and crazy emissions system. It's also CARB compliant, love NY. Lastly I never thought I'd see the day I actually installed a CEL in a vehicle that didn't come with one.
I'm 73 and I learn something everytime, I previously thought the various sensor outputs would simply go thru the ECM to the scan tool. I wouldn't have know to check voltage at the connector and compare to scan tool reading.
Time to finish putting a new front spring in my '29 Model A pickup.
Thank you
I haven't started watching yet but this is what I've been asking for. I have an 89 GMC S-15 with the 2.5L that I like to tinker on. So I'm kind of a geek about these trucks.
Sell me the ride....
Your diagnostic skills are amazing Eric!
I've lost count of how many first and second gen S10/S15's I've owned.But they're rare a hens teeth as they say now.Good to see one still on the road after all these years!You and Mrs O are something else,Y'all could have a sitcom of your very own.
Man does this bring back memories.
In 1986 I was living in Mass & I bought/ordered a new 1986 2wd S-10 Blazer with 2.8l V6 with 5 speed manual.
It had the exact same hi idle issue - but mine idles at 1200+ some times 1500+. Did this from new. Sometimes if you red lined 1st gear smacked 2nd gear & then red lined it & then put in neutral it would be at 3000RPM and stayed there for a bit. man was I glad it was a manual could you image with an automatic it would have took off on you.
I took it to 2 different Chevy dealers - but they could never duplicate that 3000 rpm issue. Nor did the fix the normal 1200+ idle. Mass had yearly inspection were I would get rubber stamped to pass. failure due to hi idle. Now had I bought it & lived in Ohio - GM would have had to buy the truck back on lemon law.
So over the years trying to fix it, I replaced every sensor on the engine with no luck - I did new engine in 1996. Distributor, Holley TBI over the years. nothing fixed the issue - as it got older the idle increase to the point it was permanently above 1500 closer to 1800. Buy tweaking the TPS volts to low side I was able to get the idle back below 1500.
I owned another 1986 GMC S-15 Jimmy V6 & 5 speed manual up to mid 1993 & it idle at 800 like it was supposed to. Only diff was it was 4wd. which the ECU does not control
But I never swapped the ECU between them. I should have but didn't.
Looking in the ECU data it said that AC was on. Um I didn't have AC, should that be off. So I think the truck was sensing AC was on so it increase the idle speed to compensate, which I believe was the 1200+ rpm idle I was seeing.
So I still own this 400,000 miles later - same issue. But in the last 10 years I did find a 1986 S-10 V6 manual in a pull & pay, I got that ECU & still had the same issue. Check the data - yep AC was set on.
Never did figure out the 3000 rpm after reline shifts though.
This was a great diagnostic video. The three (3) things that were most likely to cause the symptoms the vehicle was showing, alternator producing high voltage, a floating ground (causing a higher voltage on the ECM, like the alternator might), or a bad ECM. And, you checked/tested those pretty much in that order. This diagnostics is an almost perfect diagnostics. One that all should strive for. Great job.
The only thing that prevented it from being a perfect diagnostics, was that, well --- We did not get to eat any of your wives home cooking.
Great choreography as well. Thank you for making these videos. I know they take more work and considerably more of your time to do. They are greatly appreciated.
Omegaman69
Whhhhiiiizzzeerrrdddd???...is that you??
yeah i said that also, sounds suspiciously familiar, like the disguise isnt fooling any1, type of feels
Watching the car videos is enough, but combined with Mrs O when she has the cooking in, that's heaven right there. Great diagnostic work, I always enjoy your videos, they're easy to follow and awesome to learn from
The cat has you trained rather well. lol
& notice the voice go Saprono !
This video hit pretty close to home, I had a 92 S10 Blazer Tahoe edition that I just retired to Gary's U-Pull-It and Binghamton New York a year or so ago, I sure do miss that old girl. I had a very large tree branch come down on the front clip, had to replace the front clip which I think probably tweaked the frame a little because I couldn't keep a tire on the front passenger side to save my life but anyway as a result I started having more and more structural problems, the roof started leaking so needless to say when the transmission shit the bed I decided it was time she got retired. I love your videos and I love the effort you put into working on vehicles and helping people
Eric, I ABSOLUTEL love your videos. I wish I could find a super skilled mechanic like you iny little town here in Oklahoma. I LOVE how you ANALYZE problems and never load a parts cannon until you have verified the faulty component. I am kinda an old school mechanic and have learned so much about using scan tools to find issue by diligently watching your channel. Keep up the excellent videos and I will keep on watching. THANKS ERIC
(and thanks to Mrs. O for always taking good care of you. Her lunches look awesome..
FreddyB
Claremore oklahoma, (no rust belt)
Oologah, Oklahoma is not any better.... Countryside Diesel Repair just NW of us, is a super good shop, they will put it back to OEM condition, and they work on everything.... Fixed my 5.3L Vortec Suburban a few years ago, compressor shelled out, and they found the O2 harness eaten up by sharp teeth.... PVC valve was bad, intake manifold gasket was mostly gone... it now runs like brand spanking new
For those of us that don't look at diag screens everyday, this was an awesome video. The basics of getting the O2 sensor to work and then watch the PCM toggle between rich/lean to get the correct mixture was refreshing to watch with the vastly simplified data display. I know you were stepping back into the "bad old days" but I really enjoyed the simplicity!
I have worked on many of these (in the LLV ) for the post office(tho they had the iron duke.) The later ones with distributor less ignition have constant ignition module, and pickup failures ALL of them have pin fitment issues and the early ones have prom fitment issues BUT these trucks have 30-37 years of hard use and are still out delivering your mail every day
Still see em!
I thought all those old llv's were scheduled to be replaced a couple years ago? Was i wrong? Did something change? (maybe the unspecified virus of unknown imported origin messed with schedules?)
@@colestowing8695 Yeah, they're finally being replaced. Still probably going to be 5-6 years before they actually start taking LLVs off the streets, think they are going to return the leased Mercedes Metris minivans first
Once, I tried to get a job with the Post Office working on their mail trucks. I think the hands on test on an old mail truck is what busted me out of the job opportunity.
I was surprised that the running gear for those things were 1980s S-10 dinosaurs. The guy administering the test wanted me to look up all of the torque values and do everything according to the S-10 Haynes automotive manual. At the time, I was working fleet maintenance on newer pick-up trucks and medium duty trucks. I remember looking at the shop manager and saying: this thing has a old distributor, like who uses these things nowadays?! Looking things up in an old paper back manual also threw me for a loop.
Thanks! Excellent work! I didn't realize that scan tool would provide so much data from a 1988 vehicle. Also, I wouldn't have thought you could swap the chips like that. Gives me something new to consider as I try to keep my fleet of antique steel running!
Yep, shed a tear for us Ford Techs. No serial data access like the GM guys got pre-1990 until EEC-5 which was 1998-99 in the market I worked in. Even then the PIDs were full of anomalies like HEGO voltages in the 2v range, ECT in degF vs CHT in degC, things like that to keep you on your toes😊
That was the cool guy terminology back then...ohh yeah duel exhaust, lift kit Micky Thompson's. But Is it chipped..? Ohhh man those were the days. I mis carburetors
Watching Mr .O has given me confidence to diag more complicated problems on my vehicles… only problem now is tool availability, i could do more if I had more!!! Thank you Mr.O sir!!!
Got to compliment you on your resolve mr O, there is a reason so many of those went to the crusher. As I watched you work on that I passed out twice and had one sezure. Horrible memories I thought I had buried. Thanks
definitely a cool diagnostic on an old rig. not many of those around nowadays, i havent seen a blazer/jimmy of that vintage here in Toronto for years. all rusted out and/or scrapped due to drive test emissions.
For sure,,,& you have to have seen the favourite! A 350 swap that went global ! LOL
Yeah the old freezer fix, Been a while since I've seen that one. Remember an 85 S-blazer with this problem, the owner had a hose rigged from the AC duct to a box around the PCM to keep it cold! Good old OBD "high speed" interface... LOL
Own 2 S-10s, a '93 350 swapped daily and a '91 4.3L, but worked on several 2.8Ls, never had the pleasure of dealing with old candle stick O2 sensor but yeah fire is a MUST for removal, have several PCMs due to internal gremlin issues, hard to kill these trucks, looking at an '88 manual right now, Great Work Mr. O! Love your channel!
Bring back memory, had one in mint condition and let her go for $500. Just a dumb kid back then, great video!!!!!
Very common to have a bad PCM or connection with the PROM and it's socket on this vintage GM. I used to give them a tap test.
I was waiting on someone to mention the rubber hammer test. Had a late 80's GM that I could turn the AC on and off with a rap of the rubber hammer to the ECM.
The old tap test worked a treat.
I'm glad you were able to find that ECU. If you didn't have one, I have a spare ECU in the basement from a 1989 S10 Tahoe 4x4 auto pickup. Mine is for the 4.3L but the 2.8L proms would've worked on it. So I don't have to send it to you. :-) When you said you'd need to hunt one down in part II, I thought I'd give you a call and let you know I have one, but apparently your local parts yard is the best!
Dude, you have gotten so much better at doing videos, compared the "Dr. O" days. :-) But your videos are always very informative. Thank you for all you do. Great Channel.
Man, your grandmother must have been an Amazing mechanic 😅!!(well done Eric great job, and video) thanks for bringing us along. 😊
Ah the flipped air cleaner trick. Instant HP on a Highschool budget. 😁
Fonzi did it too !
Na man, the bumper chrome spray paint was all you needed.
Eric, you are a vehicle scientist! Love the videos and your impressive, intelligent approach to any and all problems that are presented to you.
Upside down air cleaner lid, the 'cold air intake' of it's day... 🤦
Both of them equally effective...
Yep, getting all the hot air
This was so cool!!! Thanks for bringing me along. I enjoyed the ride. God has you covered nice job Mr. O
So awesome to see you working on vintage! Fun change a pace as a viewer.
Hi Eric and the lovely Mrs. O. I had this happen to my Mothers Cavalier, after a few hrs. of back probing I came up with confusion because everything kept changing. The original problem was it would be running fine then all of sudden would backfire through the throttle body and quit running. Then the tap test came to mind, had the ECM in hand the eng. running and knocked on it with my knuckle and it backfired and quit running. To make a short story shorter, I replaced the ECM and never had another problem. I have a 1991 S-10 pick-up with a 2.8 V-6 5spd. with 224K miles and have never had any problems except the electronic analog speedo goes crazy when its cold but works perfect all summer. I think the circuit board might be at fault but every time I try to check it works fine and so it goes. Great videos Eric and sat Hi to the lovely Mrs. O.
Instead of putting it in the freezer you could spray it with caned air (computer duster) that's a lot colder than your freezer. Just an option if you want to speed things up.
Also useful for debugging the pc board itself. Flip the can upside down and dribble the liquid on individual components until it starts working again.
@@kdodds80 Might be worth opening it up and looking at it or mail it Ivan. Bulging capacitors are pretty easy to see.
@@kdodds80 I guess in this case it was cheaper but he said he got lucky that he was even able to find one. I would at least try just to see. At least LOOK at it. It might have been just a solder joint.
@keith agreed. the freeze spray is only for thermal intermittents, which is almost always joints & traces that go bad with thermal cycling. bad caps don't start working again like this, and bad ic's are usu. either good or bad from the factory and stay that way.
Nice shout out at the end.
All we are is dust in the wind.
Thanks for the lesson Mr. O.
Loving the longer videos and frequency lately! Thanks for all you do to keep us entertained.
Came for a Jeep Patriot CV replacement 5ish years ago. Staying for the brisket. ;) Love the videos, thanks for pumping them out.
Bringin' the heat!
I have a 1970's Schwinn (bicycle) which I've mostly updated to modern components. However, the one-piece crank was still OEM. To get modern clip-in pedals to function with the old crank, special adapter pieces were needed. I installed the adapters a few years ago and the bike has seen a half dozen thousand miles of use since.
Well, this season, I decided to replace the OEM one-piece crank with a sealed bearing 3-piece... I wanted to save those clip-in pedals, however, which required the removal of the adapters. The problem? The adapters will spin on for installation. But, there's no way to grip the part for removal.
I had to disassemble the pedal down to its shaft, mount the thing (bearing surface) in a small set of V-block vise jaws, and apply heat...
Without the heat, I would have had to crush the pedal shaft (bearing surface) in the vise so much, it would have damaged the machined rolling surface.
Looking back, I wonder how I ever got anything done without a smoke wrench in the shop!
Oh, and speaking of, "Bringin' the heat," I was scanning Facebook Marketplace while listening to Eric.
Someone has a pair of "Settling" tanks for sale. "Settlin'" is country-speak is for "acetylene."
Made me giggle, it did!
Glad you got em out. Another trick is padding your vise jaws with something. Leather, shop towels, etc.
GM around this timeframe was using a spray coating on the circuit boards to prevent corrosion that would actually shrink with heat cycles and over time pull on components and create lots of intermittent issues like this. I owned a couple Geo Storms from the same era with the same kinds of PCM problems. Just throwing that out there as another root cause possibility
@working_country ___ No its not. It was built by isuzu and used GM parts. The tracker and metro were suzuki
So reflowing all the solder on the board may be a solution if the pcm are not available?
Storm was an Isuzu Impulse.
yeah i was gonna say taiwan - even back than - could produce 100% reliable parts like the pcm. so, it is sad that G.M. still wanted to " get away " with something. took a long time for chrysler and G.M. to go bankrupt. In the end it was handshake deal under-the-table with the government to re-negotiate their pension obligations. in the 1960's we said " as G.M. goes, so goes the country. "
I love it when you do the test drives. I'm reminds of my time in Central NY driving around the countryside.
when he was trying to take the O2 sensor off I caught myself screaming, "use the panther pee!" 😂😂😂❤❤❤ I really enjoy his videos!
First timer here. I actually watched the whole damn thing. Funny cause my s10 doesn't have that problem. Just a damn good piece of work. Thanks
One thing I've always done is use a cutoff wheel and cut the O2 sensor off at hex nut. Then you can get a 6 point socket / impact driver etc. in there to remove it.
I cut the wire(s) and use a (very) deep socket 22mm.
I kept wondering why he didn’t slip a closed end wrench over the wire and use that instead of the open end.
Those anti-foulers got.many cars to pass inspections in the day and replaced the spiders in the old S-10's too many times to count. Love that"Pick and Pull" saves again.
Do you remember back in the day when you hooked up a volt meter to a car and counted the meter sweeps to get the codes?
Remember Shorting the connector pins on the diagnostic plug and observing the check engine light doing Morse code?
@@mikeam3871 yep gm. fords used the meter sweep. chrysler had a led handheld scanner
Appreciate the effort, Eric I have one too I have an 89 but mine runs pretty good 5 speed. Easy to work on thank you very much you're very much appreciated
I had a Cadillac of this vintage that had very similar symptoms. It turned out that the alternator ground was bad and it was under charging causing the computer to be unhappy.
"
Was it the brougham with the 5.0 307 by chance?
It’s great to see you work on and resolve issues of decades old vehicles. Thanks for posting that video.
If i remember correctly, the early 4.3s had the same wiring harness as the 2.8s. I think they literally just put in a different prom but everything else is the same. It wasnt until they went to port fuel injection that they actually updated their PCMs and harnesses and sensors etc, but i dont think the 2.8 ever got port fuel injection on the trucks.
YOU ARE RIGHT ABOUT THE 2.8 NEVER DID GET PORT FUEL INJECTION.JUST THE TOP INJECTORS.
Yes they did, the only real changes came about when the spider injection showed up in 92.
Had that exact problem. Bought all the sensors that I could from a boneyard truck including the ECM. Changed them all and lastly the ECM. Bam! Nailed it. Mine was a '93 Chevy 1500 with a 350. Love your work!
Those old ECU’s capacitors start leaking over time. Even a working used ECU will suffer the same fate sooner than later. Recapping them before damage to the circuit board is a good idea if you plan on keeping a car that old.
Good info..and by which
Matterial we can recap that
Capacitors
True, spent $1.5k having 2 Carver 1.5 amps "rebuilt", suffered the same issue.
Great video 90 GMC Safari van for 3 l solo problems and give me a direction hopping up all set to strange issues is an idea on how to track the problem thanks Eric
Great video 90 GMC Safari van for 3 l solo problems and give me a direction hopping up all set to strange issues is an idea on how to track the problem thanks Eric
OG poster meant just replacing the electrolytic capacitors. Not actually, "recapping" the old worn out ones.
It's because you are a Real Technician that I enjoy your Channel. Some garages just guess and replace.
Once I find it impossible to get parts, I start to believe the vehicle is ready to get rid of, sadly.
"just tickle this thing with a torch" I cracked up laughing off of that one 😂
I am a retired, lifetime GM dealership employee from Tech to Service and Parts Director....( a little background ). When our products had a widespread problem with drivability, they would come out with a bulletin, a widespread rattle problem, guess what?...Yup, another one page bulletin from the engineers. The point I am getting at is the fix is usually a sheet of paper with the "how to"......Here is the kicker, guys.... The drivability bulletin on the 2.8 in the late 80's was a 36 page book. A freaking BOOK.( I have one as a souvenir ). It was mostly 2.8 V6 engines in cars, but, it was always the 2.8. They never ran perfectly, like the 3.8 V6 did.........
Got a good laugh over the "dash lights" 🤣
84 - 86 Buick roadmaster had a recall on the proms....I got involved with that program for while back in 88.....working at a dealership in NJ..,..keep up the good work bud
My first car was an 85 s10 with the big 2.8. Was a POS 20ish years ago. Can't believe this thing is still on the road.
My current daily driver, grocery getter, dog hauler is a 96 S10 Blazer. It’s got the big 4.3, no rust anywhere, 110k, and mine too has a fragrance, … wet dog! It was free and I love it!
I bought a 84 S-10 with 2.8 new. Serviced every 2500 miles and the engine was junk at 70,000 miles
The 2.8 was one of the worst motors ever built.. just a complete dog.
@@forindooruseonly646 i disagree. I pretty much beat the average vehicle off the line here. I've an 86 2.8 with TBI. No work done. Automatic. Still OG engine with just over 200k miles, my DD. Now the manual version, they're dogs but that's a trans issue, not engine.
@@forindooruseonly646 Bang Bang,,,,your died !
It amaze me, a simplicity to check all grounds and voltages into PCM, even the reference voltage circuit. It reminds me from other of yours valuable videos, a clean and very neat task to verify each in and out wire from a BCM module . At the end may be a variable contact from a peeled-piched cable to ground, my fat bet was in the reference voltage circuit. Thanks Mr. Erick O. Wish you good luck as always.
The smaller chip is the "calpak" -- basically a matrix of resistors to let the vehicle run in limp home mode when the main EPROM fails.
I just wished every town had an Eric O. Well, at least mine. Nice job Mr O.
Got 1988 Ford Maverick 4.2 petrol or a Nissan Patrol rebagded, just replacing original alternator, parts ready but a public holiday for the Queens funeral here in Australia, I am in the Northern Territory and live like a hermit 135ks away from the spare parts place, what a hassel, I have charged up my tractor battery as the car battery has also died and hopefully I will be able to get to the spare parts tomorrow and back to where I live to replace it, luv the car, use 4wd nearly every day prospecting in country most people will never see. Have a good day, really enjoy your videos on my days stuck at home.
I’m betting leaky caps on the OG circuit board. Great job as usual, Eric! I drive a 1988 Civic to work every day. Good to see some old OBD0.
There's no electrolytic caps on this vintage. Only ceramic.
@@CubasAutomotive Same vintage as the old ford EEC-4 system. They had a bunch of electrolytic caps that get leaky. (Shago on his channel shows basic repairs and the damage leaky electrolytic caps cause.)
Not saying wrong or right, but yes..older PCM's can and do use electrolytic's in some models.
@@commietube_censorship_sucks wrong. I have opened up 3 when I replied to someone else's comment. I work on these ALL the time. You want pics?? Lol
@@commietube_censorship_sucks all 3 are S10 ecms (without the eeprom chip, as they were reused) 85 to 94 vintage.
@@Tedybear315 yes, some do use electrolytic capacitors. Agreed. Not in this case. I've done all sorts of board repairs too. TVs, PCs, ECMs, and other modules.
ABSOLUTELY LOVE THE INFORMATION ON HOW TO BACK PROBE THESE COMPUTERS AND THE TEST LIGHTS AND T-PINS TO BACK PROBE!!!!!! DUDE YOURE A BLESSING TO A YOUNG TECH LIKE ME!!! GOD BLESS FROM GEORGIA
These were great basic trucks... the V6's were decent power, and pretty reliable. and easy to work on.
It's kind of amazing to me that it ran at all.. with that much corrupted or missing data/ feedback.. sometimes simple is better.
Makes me want to go find one of these.. be a great basic practical truck.
I like that test with the "sniffer" to check for evap core leaks. The test tool has lights for leak checks which is great, and the oil injection tool looks like a big help.
Good to see you work on an old car. Problem sounds like mass air censer. I had the same problem with my 87 Camaro. Three dealers couldn't figure it out, and the manufacturer couldn't care less.
Always nice to see Mrs. O, She does treat you well.
These used speed density programming, computer used the map sensor and tps reading to calculate fuel while in open loop. After it went into closed loop, it'd use the O2 sensor.
@@dave1135 Those “we’re” the days…..never to return ! Too bad! LOL
that is a skillfull spouse! Congratulations on what looks like good coupling!
At 32:17 I was wondering if there was a heater hose under the dash near the computer.
At 41:23 I was wondering if the internal regulator might be failing, but I'm an electrical engineer and that's not something that I would expect a normal automotive tech to dig into.
-. Nice job with the O2. One thing I might have added to what you did, was to put some nickel anti-seize on the threads of the O2 bung. I found that it makes a big difference on parts that are hard to get out because they aren't replaced very often, when they are replaced the second time. If this truck had been typically rusty it wouldn't make a difference, but it looks like this owner may restore and preserve the truck for a long time.
If they don't fluid film it it'll only last a couple years up there at most.
Having moved to Texas from WNY 45 YRS ago... I have the brisket thing down. We don't have kaisers/wecks here. I make my own wings... but I do miss beef on wecks. :-( You make me sad, Eric! Haven't seen you in a few months. I guess the algorithm has come back around. Cheers, guys!
FYI: It is not unusual, in electronics troubleshooting, to use "spray cooler" to cool off components to see if they react to temperature. (any quick-drying spray which does not leave residue would work...perhaps brakleen?) My bet for this one is cracked solder-joint which just needed to be re-flowed.
It's almost definitely dried out capacitors and/or cracked solder joints around component leads and connector pins. I've repaired some old ECM/PCM modules before. Sometimes the capacitors also leak electrolyte onto the board and corrode the traces. Cooling down the board and gaining functionality indicates that it's not corroded, though. Freeze spray is great, but it also requires direct access to the PCB.
REALLY love this in depth dive into troubleshooting on some seriously wacky behavior. Incredibly thorough work as usual for Mr. O which results in yet another W