Just want to say that it's fantastic to watch a video where someone actually correctly troubleshoots a problem completely. No guessing, no parts swapping, just systematic elimination of possible causes. Your thoroughness and clear explanation is very much appreciated. I've got a '97 4.3 and I now know after watching this video what my problem more than likely is. Sadly it's a bit too late for my cat as I think the fuel dump has overheated it as it's rattling like crazy. Still, thanks a bunch! Your students are lucky to have such a fine teacher.
Thank you Danner... one of the best vids I've seen. Today I learned. I've watched about 7 Vids on this topic and hands down, this one was best explanation!
thanks again for the videos wouldn't know where to start. everything is checking out as you are describing. pressure going to 60 and back, put a vacuum test staying on the green snap the throttle it goes to 0 and back up to green give it gas and its staying on green as gas goes up needle moves just a bit to about 23. bought a map sensor, tps and iac. I'm on the iac part of it. took it off twice and is all the way extended. that's where I am now. oil pressure staying on 50. took off O2 sensor black, snapped throttle still bogs down. not giving up thanks man for sharing that is really a blessing.
what is your upstream O2 sensor indicating at wide open throttle? It should be pegged rich (over 800mv). If it is, we then move away from fuel as the source of your bogging down issue
Hi Paul, love your work. I am learing allot from you one video at a time. I always replace the lines when I replace the spider. Standard HK11 very tight fit. At present time I am fighting CPI problem on my 1994 Astro van that I have owned since new. At this point in time (5/28/2023) I can no longer buy CPI for affordable price. I can send my core CPI to Rock Auto or others but the cores are so rare that I want to fix my own. I replaced my regulator but did not know I could adjust it using T10 screwdriver or bit and the new regulator had very low pressure. I plan to try and adjust it and your video is helpful. I had 75 psi when I blocked the CPI return line but I didn't test the check valve. I have a new Delphi fuel tank sending unit that includes the fuel pump I plan to install soon. I think my CPI Maxi injector is leaking intermittently. I cleaned my MAXI injector and that helped but I am looking to buy a new MAXI injector and the six pack gasket that is under the MAXI injector if I can find a source to buy a new one. One video showed if you spray compressed air across the CPI regulator if not leaking it may leak. Your video did not show I could adjust the pressure using T10 so you may want to update and edit your prior videos if you have time. Thanks for all you do and sharing your faith via video.
75 is a little on the low side. If you have wide open throttle, high rpm hesitations and lean conditions, that pump may need be keeping up. If your regulator is adjustable, set it to 62 psi for your no vacuum pressure (koeo prime or wide open throttle) and 54 psi at idle (with vacuum). Give or take 1-2 psi for gauge differences
hey Scanner Danner! I'm on a 19981 Chevy Truck that I'm dealing with. I have the pressure gauge hooked up and I have an immediate drop of rest pressure down to 0. haven't taken off the intake yet but ur video definitely confirms my suspicion. this truck too has rich codes, hard to start and raw fuel smell. awesome vid, keep up the good work!!!!!
+Pdubforever1 did you see part 1? I show how to isolate where the leak is by pinching off the fuel lines, but it sounds like you are correct, it's most likely the reg based on your symptoms
+ScannerDanner yes I did. and I will also do that. Real quick, just wanna let you know ur videos help me alot. your insight and knowledge is way great. I'm definitely a big fan!!!
Awesome tech service trouble shoot Paul . I have a 1997 Blazer 2WD with the "W" code engine...(4.3 L) V6 . And i had pretty much the exact same symptoms....long crank times (needed to press down on the accelerator while cranking to get it to start , poor idle and a very distinct hesitation of the engine during part throttle driving , which i might add can be easily confused with a transmission problem . I also had the "SES"/"Check Engine" light on and randomly flashing as well . Awesome videos .
Oil contaminated with gas also not good for lubrication/protection-- Paul, i would like to say you/your school make the best videos here, extremely thorough and well explained
I just did one of those spider replacements and the nut kit with two hoses you left in place on a 95 blazer. It was running rough until I did this replacement. Not too hard to do.
GM had live data all the way back to 1983. There are plenty of manufactures that had live data before OBDII, you just needed the correct scan tool to view it.
Paul, 6/11/2023 5:30 EST update. I took your feedback to heart and I pulled my CPI upper intake plenum for inspection and I discovered that The CPI feed line had popped off the cpi. When I replaced the CPI supply and return lines with Standard Ignition PN # HK11, I failed to remove the old o rings from the CPI core so I had double o rings and the retainer clip was not seated well enough. I tried to remove the old o rings from the CPI core but failing that I just left the old o rings in the cpi core and no leaks. In the past I replaced the cpi regulator with new standard ignition PN # PR 484 and adjusted using T-10 screwdriver for 62 psi (clockwise for higher) with key on engine off (KOEO). Pressure gauge held pretty well so I did the line block test again and found pressure held with supply line clamped off. I have a new fuel pump and fuel sending unit and I plan to replace soon as I have time. Today I got email that company I trust had reconditioned CPI and I ordered it for $200 with core fee. If I get the CPI and its good I plan to replace it with the more recent one and return the one I have for reconditioning. I installed and shorted out the ignition system and found all the poppets are spraying okay enough for me to use the van to haul my mangoes to the packing house a few miles away. I double checked the fuel pump and found 90 psi with return line clamped. I am putting the van back together now and hope to have it running soon. The supply line when it was loose had dumped lots of fuel into cylinder # 3 and when I did compression test I had a fire as gas shot out from # 3 and I failed to short out the igntion system and I have damage to the plastic lines for control of climate and need ideas how to repair those small plastic vacuum lines that burned in the fire. Lucky I keep two big fire extinguishers handy. Thanks for your videos and help.
@ScannerDanner I was going to 2nd the comment about not having to pull the assembly out just to do the regulator, but in your case I see where it's easier to modify it on the bench if the new part doesn't fit. Your videos are really great - keep up the good work!
@fivefortyeye540i 230 F, quick test for PCM control of fan relay is to unplug the ECT sensor. The PCM will store a DTC and turn the fan on as a default.
@foxholewilly Absolutely, however I am not worried about it unless it comes back with low power complaints and or a cat. code. So far so good though. Truck is running great! The camera is a Panasonic HDC-TM60.
@Joe Alvarado I cannot reply to your question or comment on your channel. You need to change your settings my friend. Hopefully you'll read this, the answer is no, you do not need to adjust that screw, it is preset for the correct pressure for your engine.
Hi , watching the video, I realized that this type of regulator seems to be the same type that I have on my car, my question is that I have a pipe connected to the regulator but which connects before the throttle, so I will not have depression at this place. ?
Question on the injector? All four screws need be tighten all the way right? Also plastic ring top does it sit just flush or does it have to go as far as it can? Thank you.
@fivefortyeye540i Good question, but it is neither, although easily confused with the switch inputs that I applied those terms to in my book (Section 2). What this relay is, is ground side switched (Section 3). I use the terms pull-up and pull-down with switch inputs, not output solenoids, as this relay technically is. Remember inputs are being "watched" and outputs are being "controlled".
All seems to be fine, but before to put the uper part of intake manifold, I would like to know if I need to adjust the new Fuel Pressure Regulator I just put there just to be sure.
Hi I have Honda Odyssey 2.4L k24z2 (Japanese version) in Australia. Car run fairly fine but sometimes I noticed starting car takes little bit long time and I can see negative (0 to -20) STFT and LTFT reading from OBD scan tool. And at idle, fuel trim hits the bottom. I also noticed fuel smell from engine oil too. I have changed O2 sensors and cleaned other sensors before this video. Do you think it is caused by bad FPR? I just ordered Fuel Pressure tester gauge for checking but what my theory goes to FPR after watched your video.. what do you think?
I have an absolute no start. I have fuel pressure from the pump. Could the regulator have gone that bad? 95 4.3 vortec in a blazer S-10. Also I have replaced all the components in the ignition system.
Are you referring to not cleaning the INSIDE of the intake manifold? Only a "hack" would clean that part as it is supposed to be "dirty". If you did clean that part of the intake within a few hundred miles of driving PCV gases will make it just as black as you see in the video. What would be pitiful is after cleaning that part of the intake you dumped all of that crap in the bottom end of the engine.
@Thank you!! They kicked on at 225, just out of curiosity is that cooling fan circuit a pulldown circuit or pull up.. I figure sence the the ECM pull the relay to ground. Or am I all wrong about this..
ScannerDanner hey rob,i have a astro 4.3 v6 cpi and it was bogging down like crazy to the point it will stall..so i put in a brand-new spider and its still doing the same exact thing! What thw hell can it be? I have replaced the map,iac,tps,all the plugs and wires etc...i start it,it starts right up and idles perfect,as so as i touch the gas pedal it boggs down and sputters and wants to stall..what else would make it do this? I feel like every part i replaced was for absolutely nothing because its still doing EXACTLY what its always done..fuel pump goes on for about 4/5 seconds i can hear it humming..i cleaned the egr..i need ur help with this one man please lol...its driving me crazy!! The vans all custom,interior,45 inch plazma tv,blueray dvd,22 inch rims,the things badass!! 92,000 original miles,one owner before me..new starter,belt,and everything else i named..it just kills me that its so mint and i cant figure out what else it can be..pisses me off! LOL..i put a new gasget when i did the spider too..made sure everything was all plugged in where it belongs..im stumped rob..what do u think it can be??? If u can send me ur number so i can send u some videos that be great.or i can text u.u have an email? Anything dude,i really need ur help.i know u can help me figure this one out.. ur the best ive seen on TH-cam by far!!! Great at what u do!! Thanks man,any help would be great! Thanks, David m, from Connecticut😀
@ScannerDanner Swtich inputs = pull-up or pull-down. Output solenoids (relay in this case) = ground side switched or power side switched. It is easy to call this a pull-down design as the control wire voltage drops to ground when the relay is turned on. I just try to keep my students from calling it that so as to not confuse inputs and outputs.
One of those fuel lines broke on me and all of a sudden the motor just seized up.. I thought my batteries was dead cuz it wouldn’t crank so I called someone to give me a jump and still wouldn’t turn over so I started to take the spark plugs out and as soon as I pulled number 3 it started pouring out gas the cylinder had filled up with gas from that broken fuel line.. the reason I’m telling you is there is a lot of people out there that think there motor is blow cuz they think it’s seized up but really it’s just vapor locked..
I will thumbs up & click on yours ads like I previously said to say thanks for taking your time & effort for making these videos.Thanks so much Dan,You rock!
no, you can use your multimeter. It would be the black wire on the O2 sensor side of the connector that is your signal wire. Just remember it will only be rich DURING the acceleration period at wide open throttle. As soon as you let off the gas, the engine will decelerate and the ECM will shut down the injectors momentarily and it will go super lean. Super important test for us right now. I want to know if your bog is fuel related or not.
@scannerdanner Do you know what temp would kick on the fan on this 98 Buick century 3.1 I thought at 220f it should have kicked on live data showed 106 c that's about 220 if not more. So I poweprobe the fan it works checked fuse it's good. Power probe the relay it clicks. I'm starting to think ECM is not pulling relay to ground.
Awesome video! doing work on my 1995 gmc jimmy, have done all the pressure tests, i'm going in. however, i have a question, Did you have to adjust pressure on fuel regulator? it has an torx screw inside for further adjusting, looking forward to your answer. and thank you in advance.
I think I have a bad regulator because mine does the same; climbs to 62 psi then drops. While I'm in there replacing that, should I just replace the whole spider injector system too? My main concern is that I don't want to have that fail later on. Anything else you recommend doing while it's tore apart? Thanks a lot these videos will help a lot!
@FabricationStation36 Mostly students cars, but I do work for a few garages too. I am willing depending on what you have. Obviously my only interest is on the electrical side. Check engine lights, misfires, no starts etc. Also you can't rush me as educating my students comes first and fixing the car comes second. We can talk, go to my website and email me through there. My response will be from my home email address.
It's me again Wayne with the 1994 s10 4x4. Chevy GMC 4.3 vortec vin number W. Put brand new spider in truck run fine it's been about month law kinda missing but I put everything new from icm rotor cap wires plugs put all that stuff on there before I fount out it was spider with fuel test was loosing pressure had about ,63 psi. Might have fowled plugs going to replace them they said gap was 45 but with vin W supposed to be at 60.. but yesterday I pulled up and it started smelling bad gas just out the blue done it twice just wondering if it's the TPS I hope spider and going bad ain't had it on a month got hesitation and little miss in it you can feel the miss when you go down the road but when you push gas throttle like it don't won't go nowhere found down the road you can push it but it don't kick down or even pick up speed I'm check timming to but it will fire right up these vortec never have another one
It does look like you could have changed the regulator without pulling the center out and pop injectors, is it possible ? Fantastic Vid. Looking forward to a vid on L&S term fuel trim functions.
got it, but it has to be later on the week were getting hit with a freeze and I do not have a garage I have been raising the van with a jack so its a slow process thanks again ill leave a comment when ready
@94vettelover2 Thanks but just click on the ads if you are truly interested. I believe your IP is tracked when you click so multiple clicks just inflate the numbers and then they take it away from me at the end of the month.
thanks for the fast response (awesome) its a 1995 astro van 4.3 cpi changed fuel pump getting 55psi but when it warms up surges and when you snap the throttle it bogs down.
during the bog down snap throttle test, what is your fuel pressure? It should be about 60 psi during the rev up. Important that you are looking at the gauge DURING the increase in RPM because psi will drop as soon as you let off the throttle (normal)
Great video! Very informative, I learned a lot. I have a 96 2500 suburban with a 7.4l hard starting. I can see fuel seeping around the plenum gasket. So I know I have problems. More then usual poor fuel mileage. I didn't buy it for economy, but even still bad fuel mileage. Anyhow great video, I subscribed to your channel. Thanks again!
Replaced my regulator and solid psi now. Still having random shut off and wont restart. It does crank and i have spark in the distributor. Im thinking i need to replace the whole spider assembly with the new aftermarket electronic one because i have good pressure and a new fuel filter and want to avoid future issues with this faulty assembly. Would you agree or do you have any information for me to might help? TIA
+Andrew Love wiggle the two pin connector for the injector harness (blue and red wire). If it shuts down, pull the intake back off and tighten the injector terminals
I pulled my intake apart and checked for any leaking and loose connections. No leaks with the pump jumped and I have 59 psi while it is jumped. It drops to around 50 psi within 30 seconds and holds around there while slowly dropping. Could my fuel pump be failing? It starts up with no issues on a cold start. While idle it is dying at around 10 minutes and then I cant restart it for a little while. Then it acts like its choking when I restart it. I have replaced the fuel regulator, fuel filter, spark plugs, and made sure I have spark. Also, my o2 sensor is working properly. This problem has been so sporadic and now my truck wont stay running at all. I'm sorry for bothering you. I am just trying to get my daily driver back up and running. TIA
I have a 1994 s10. It maintains 62 psi while cranking but won’t fire it will drop 8 psi in 10 minutes . But when i spray gas into the intake it will fire up and run for a second and cut off. Do you think the spider is bad or what else could it be.
You need to verify injector pulse. Disconnect the two wire (red and blue wire) connector and put a test light in between the two terminals (DONT LET THEM TOUCH EACH OTHER) and crank it and see if the light flickers on and off during cranking. My money is on that it does not.
I started to wiggle the connection to the injectors and it fired up, i could pull on the wires to make it run better or worse and finally got it where it runs perfect so i can get it to a better place to get a new connection. Thank you so much! My rig is fixed!!!
@@hunterharris37 If that is the case. It is not fixed. There is a connection inside of the manifold that goes right to the injector itself. Those terminals need tightened up. You'll have to pull the upper intake to fix it.
Having more issues and figured i would come back to you! When i jump the fuel pump i get a constant 60 psi. As soon as i turn the pump off it drops immediately to 10psi. I have tried to isolate the fuel pump and the return line and i can’t find where it’s bleeding off. I replaced the fuel pump and the pressure regulator but not the whole CPI unit. Rig is running really sluggish and long hard starts. Any other advice?
Glad u said they all fire at the same time nobody else said anything about that. Also anyone know I found rtv around the the electrical connector did it come like that
well, I respect your opinion for me that guy is a genius. I have learned a lot diagnosis Technic and I have decrease my math jajjaaj. how wonderful day I absorb good things and this guy is providing 99% good info and 1% on this vehicle not cleaning there ho well it proves nobody is perfect.
Faulty regulator or restricted return line. Remove return line and install a new temporary line and run it into a gas can. Recheck psi. If still high, change regulator, if now normal, find the kink in your return line
ScannerDanner: for someone with quite a bit of time under the hood with DIY mechanic projects, how long would you estimate it would take to get everything loosened, disconnected, etc, and the the air intake plenum off? I've never taken one off. Also, does the plenum gasket need to be replaced every time the plenum gets pulled off? For example, say I opt to just buy the inlet/outlet lines, and the fuel pressure regulator, take it all apart and find out the injector assembly hoses are cracked and need to be changed. If I put it back together with the new gasket (and the other two new parts) can I drive it around while I wait for the spider assembly to come, and not worry about buying another gasket. I'd rather not dish out the money to buy the assembly if I don't have to, but don't want to get everything apart and find out I have to order a spider assembly and have to wait with a completely non functional car, and on top of it buy another new gasket. Hope that last question made sense. Would it just be worth it to buy everything together and replace it all since I'm in there, all at the same time? Thanks!
It is not a hard job at all and it is no big deal to go back in if you have too. And I have re-used the gasket, but not the original one. We had a new reg. leak and had to go back in 2 days later.
Thanks for the reply, Scanner Danner. I put a fuel pressure gauge on, ~62 at key on, held for more than 20min within at 62psi (is it possible it could have been held open/close). I turned it on and opened the throttle, it would go up to about 65 than drop to about 57ish after letting throttle close. By that time I had already bought the fuel pressure reg. and a gasket. I dicided to just pull the plenum off and worse case if nothing was washed, I'd just swap the gasket. Regulator side was all washed with pools of gas. Inlet side was pretty dry and black. I keyed on, and nothing leaked. I swapped out the FP Reg, leak tested, keyed-on, pressure dropped from 62 to 58ish after that, but stayed at 58 for a long time. I put everything back together and it seemed to be running a bit better, but as soon as I stop at a red light, do a right on red and then go to accelerate, it starts missing and sputtering (right around 20-30mph) acting like it wants to stall. In park, it's fine. I have new plugs (Cyl 2 was completely burned up: no electrodes -that may be from bad threads as it is hard to hand tighten) cyl 4 and 6 were caked (2 4 6 are on regulator side) 1, 3, 5 were clean; new fuel filter (old one I couldn't hardly blow through), new ignition control module (old one was arcing); PCV valve rattles and I cleaned that out a bit with some cleaner. I"m not really sure what else it could be. Sorry that was a long reply, but you caught me right after washing the grease and manifold soot off. :) Thanks again!
wiggle the wiring harness where it goes into the intake. Should be a red and blue wire. This connects to the injector inside of the intake. If the engine stumbles when you wiggle these wires, the connector is lose on your injector. (common issue)
Bart Black I wanted to follow up after all my car problems got resolved. I did a lot of reading and research via youtube, forums, etc: I finally got my hands on a multimeter and went through and tested EGR valve, TPS sensor, IAC valve, and MAF sensor. Everything was as should be and I couldn't figure out why my car was still wanting to stall out during acceleration. I finally got fed up with it and took it to a mechanic yesterday. He was impressed with the list of things I had tested and/or replaced. It turned out that the distributor cap, the rotor, and the spark plug wires were corroded, burned up and barely producing any spark. And the Distributor itself was rusting. In my defense, the items I replaced did need it (ex-clogged and old fuel filter). About a month prior to my problems starting, I had purchased a set of spark plug cables with the ignition control module. For the last 2 weeks I've been thinking, "Maybe I should pull the wires and replace them with the ones I just bought." But the first mechanic had told me that the car was producing great spark and that the wires didn't look like they needed replacing. I don't know if he actually ever checked them. I'm a bit embarrassed that I did all this diagnostic work, and never pulled the distributor cap or the cap-end of the wires. I based it on the 1st mechanic and never confirmed what he told me. Luckily replacing the cap and the rotor and the wires solved the problem, without replacing the distributor. I guess the point is, my dad always said "start with the simplest, most basic, and cheapest part to replace, and work your way through to the more complex parts, because a lot of times it could just be a loose wire or a blown fuse." HE was right! For all those DYIers, don't under estimate the basics, and verify for yourself what someone may have told you. I could have had this problem fixed 2 weeks ago. Anyways. Carry on!
What ? they fire at the same time? so it wastes gas and injects it at wrong times on some of the cylinders? Another reason to use the upgrade injector system. I know the new system has actual injectors where the poppet valves go, it makes me wonder how the new system can have individual injectors open if system was designed to give electrical signalling for all to open. I'm a little skeptical of your claim actually but I realize this is th eolder system with that aluminum intake manifold, so maybe it doesnt apply
Intake valve openings are the key to understanding how and why this system can work. There are other injection systems that have one driver for the entire engine. These are called group fired injection systems. This is no different, they just figured out how to do it with one electrical injector.
Yep!! It's good and clogged my guess it had missfire and was ignored and plugged the cat.. That's what I get for not having confidence in what I have learned from ur teachings..
I believe I got to 5 or 600. not very sure since meter kind of going up and down. ill have to double check again didn't check my voltage from the ecm. ill try to get a better reading thanks again.
yeah, a voltmeter is a little slow to update, was that on a dead rev in park or were you test driving it? My suggestion would be to rig up a jumper wire to the O2 signal wire and then run it inside the truck and take it for a test drive. This will allow you to hold it at WOT for a longer period of time than what a dead rev would allow, giving your meter a chance to update and give us a true picture of what is going on. Of course the alternative would be to use scan data if you have one that will give you O2 mv
Silly design. These engineers must think it's pretty funny putting the regulator in such a stupid spot. I'd simply change mine in 5 mins with a used one IF it was a 'normal' design... guess it'll stay the way it is. After gas prices jump up more I'm sure many of these gas suckers will be retired anyway like mine will be in the Spring... it has 362k on it anyway. Good vid.
So you said that the injectors shoot out all at the same time so that means that is a lot of fuel wasted instead of saving fuel with this system so the Chevy engineers are a piece of crap, I have an 02' Chevy Astro van and I've seen that the fuel pressure regulator is inside and I just got really angry that the part is inside the plenum this is a PIECE OF SHIT I will never buy another Chevy
Interesting that you are teaching students how to do repairs, yet you make excuses for not cleaning up components & surfaces! Nothing like an educated "hack"! Pitiful!
![How to Test for a Stuck Open Fuel Pressure Regulator! [A ScannerDanner Premium Lecture]](http://i.ytimg.com/vi/ZG8rMJwILxA/mqdefault.jpg)
Just want to say that it's fantastic to watch a video where someone actually correctly troubleshoots a problem completely. No guessing, no parts swapping, just systematic elimination of possible causes. Your thoroughness and clear explanation is very much appreciated. I've got a '97 4.3 and I now know after watching this video what my problem more than likely is. Sadly it's a bit too late for my cat as I think the fuel dump has overheated it as it's rattling like crazy. Still, thanks a bunch!
Your students are lucky to have such a fine teacher.
+Steve Harris (65Westfalia) Thanks so much!
Simply the best. If you have not ... Get the book. It has procedures that saves hours in our shop. Thanks Paul
Thank you Danner... one of the best vids I've seen. Today I learned. I've watched about 7 Vids on this topic and hands down, this one was best explanation!
Awesome thank you
thanks again for the videos wouldn't know where to start. everything is checking out as you are describing. pressure going to 60 and back, put a vacuum test staying on the green snap the throttle it goes to 0 and back up to green give it gas and its staying on green as gas goes up needle moves just a bit to about 23. bought a map sensor, tps and iac. I'm on the iac part of it. took it off twice and is all the way extended. that's where I am now. oil pressure staying on 50. took off O2 sensor black, snapped throttle still bogs down. not giving up thanks man for sharing that is really a blessing.
what is your upstream O2 sensor indicating at wide open throttle? It should be pegged rich (over 800mv). If it is, we then move away from fuel as the source of your bogging down issue
Great one. one of the biggest issues ... "gremlins" on this particular motor system. Thank you.
Great video. Job well done. The best video I’ve seen for this type problem.
Hi Paul, love your work. I am learing allot from you one video at a time. I always replace the lines when I replace the spider. Standard HK11 very tight fit. At present time I am fighting CPI problem on my 1994 Astro van that I have owned since new. At this point in time (5/28/2023) I can no longer buy CPI for affordable price. I can send my core CPI to Rock Auto or others but the cores are so rare that I want to fix my own. I replaced my regulator but did not know I could adjust it using T10 screwdriver or bit and the new regulator had very low pressure. I plan to try and adjust it and your video is helpful. I had 75 psi when I blocked the CPI return line but I didn't test the check valve. I have a new Delphi fuel tank sending unit that includes the fuel pump I plan to install soon. I think my CPI Maxi injector is leaking intermittently. I cleaned my MAXI injector and that helped but I am looking to buy a new MAXI injector and the six pack gasket that is under the MAXI injector if I can find a source to buy a new one. One video showed if you spray compressed air across the CPI regulator if not leaking it may leak. Your video did not show I could adjust the pressure using T10 so you may want to update and edit your prior videos if you have time. Thanks for all you do and sharing your faith via video.
75 is a little on the low side. If you have wide open throttle, high rpm hesitations and lean conditions, that pump may need be keeping up.
If your regulator is adjustable, set it to 62 psi for your no vacuum pressure (koeo prime or wide open throttle) and 54 psi at idle (with vacuum). Give or take 1-2 psi for gauge differences
hey Scanner Danner!
I'm on a 19981 Chevy Truck that I'm dealing with. I have the pressure gauge hooked up and I have an immediate drop of rest pressure down to 0. haven't taken off the intake yet but ur video definitely confirms my suspicion.
this truck too has rich codes, hard to start and raw fuel smell.
awesome vid, keep up the good work!!!!!
+Pdubforever1 did you see part 1? I show how to isolate where the leak is by pinching off the fuel lines, but it sounds like you are correct, it's most likely the reg based on your symptoms
+ScannerDanner yes I did. and I will also do that.
Real quick, just wanna let you know ur videos help me alot. your insight and knowledge is way great. I'm definitely a big fan!!!
+Pdubforever1 thanks brother
Awesome tech service trouble shoot Paul . I have a 1997 Blazer 2WD with the "W" code engine...(4.3 L) V6 . And i had pretty much the exact same symptoms....long crank times (needed to press down on the accelerator while cranking to get it to start , poor idle and a very distinct hesitation of the engine during part throttle driving , which i might add can be easily confused with a transmission problem . I also had the "SES"/"Check Engine" light on and randomly flashing as well . Awesome videos .
Oil contaminated with gas also not good for lubrication/protection--
Paul, i would like to say you/your school make the best videos here, extremely thorough and well explained
Good stuff Paul, as usual. The Help! line is made by Dorman for those that don't know.
I just did one of those spider replacements and the nut kit with two hoses you left in place on a 95 blazer. It was running rough until I did this replacement. Not too hard to do.
GM had live data all the way back to 1983. There are plenty of manufactures that had live data before OBDII, you just needed the correct scan tool to view it.
Paul, 6/11/2023 5:30 EST update. I took your feedback to heart and I pulled my CPI upper intake plenum for inspection and I discovered that The CPI feed line had popped off the cpi. When I replaced the CPI supply and return lines with Standard Ignition PN # HK11, I failed to remove the old o rings from the CPI core so I had double o rings and the retainer clip was not seated well enough. I tried to remove the old o rings from the CPI core but failing that I just left the old o rings in the cpi core and no leaks. In the past I replaced the cpi regulator with new standard ignition PN # PR 484 and adjusted using T-10 screwdriver for 62 psi (clockwise for higher) with key on engine off (KOEO). Pressure gauge held pretty well so I did the line block test again and found pressure held with supply line clamped off. I have a new fuel pump and fuel sending unit and I plan to replace soon as I have time. Today I got email that company I trust had reconditioned CPI and I ordered it for $200 with core fee. If I get the CPI and its good I plan to replace it with the more recent one and return the one I have for reconditioning. I installed and shorted out the ignition system and found all the poppets are spraying okay enough for me to use the van to haul my mangoes to the packing house a few miles away. I double checked the fuel pump and found 90 psi with return line clamped. I am putting the van back together now and hope to have it running soon. The supply line when it was loose had dumped lots of fuel into cylinder # 3 and when I did compression test I had a fire as gas shot out from # 3 and I failed to short out the igntion system and I have damage to the plastic lines for control of climate and need ideas how to repair those small plastic vacuum lines that burned in the fire. Lucky I keep two big fire extinguishers handy. Thanks for your videos and help.
glad you are okay! That could have been really bad. Also glad you got it figured out
@ScannerDanner I was going to 2nd the comment about not having to pull the assembly out just to do the regulator, but in your case I see where it's easier to modify it on the bench if the new part doesn't fit. Your videos are really great - keep up the good work!
can the regulator be replaced without removing the cpi unit poppets etc
@fivefortyeye540i 230 F, quick test for PCM control of fan relay is to unplug the ECT sensor. The PCM will store a DTC and turn the fan on as a default.
@foxholewilly Absolutely, however I am not worried about it unless it comes back with low power complaints and or a cat. code. So far so good though. Truck is running great!
The camera is a Panasonic HDC-TM60.
@Joe Alvarado
I cannot reply to your question or comment on your channel. You need to change your settings my friend.
Hopefully you'll read this, the answer is no, you do not need to adjust that screw, it is preset for the correct pressure for your engine.
@Bonfield2002 Yes, it is possible, I don't know why I didn't do it that way in the first place?
the intake valve takes care of that. the injector fires one time per crank rotation on this design so two times before each intake valve opens
Hi , watching the video, I realized that this type of regulator seems to be the same type that I have on my car, my question is that I have a pipe connected to the regulator but which connects before the throttle, so I will not have depression at this place. ?
Question on the injector? All four screws need be tighten all the way right? Also plastic ring top does it sit just flush or does it have to go as far as it can? Thank you.
Plastic ring? Injector screws? I'm so sorry man, it's been such a long time. Can you give me a time stamp?
@fivefortyeye540i Good question, but it is neither, although easily confused with the switch inputs that I applied those terms to in my book (Section 2). What this relay is, is ground side switched (Section 3). I use the terms pull-up and pull-down with switch inputs, not output solenoids, as this relay technically is. Remember inputs are being "watched" and outputs are being "controlled".
Best video out there on this system hands down!!!! Thx S.D
All seems to be fine, but before to put the uper part of intake manifold, I would like to know if I need to adjust the new Fuel Pressure Regulator I just put there just to be sure.
No adjustments needed
Hi I have Honda Odyssey 2.4L k24z2 (Japanese version) in Australia. Car run fairly fine but sometimes I noticed starting car takes little bit long time and I can see negative (0 to -20) STFT and LTFT reading from OBD scan tool. And at idle, fuel trim hits the bottom. I also noticed fuel smell from engine oil too.
I have changed O2 sensors and cleaned other sensors before this video. Do you think it is caused by bad FPR?
I just ordered Fuel Pressure tester gauge for checking but what my theory goes to FPR after watched your video.. what do you think?
I have an absolute no start. I have fuel pressure from the pump. Could the regulator have gone that bad? 95 4.3 vortec in a blazer S-10. Also I have replaced all the components in the ignition system.
I found the videos very informative , thanks for taking the time to make them . Now does this works on an 2002 astro ?
Are you referring to not cleaning the INSIDE of the intake manifold? Only a "hack" would clean that part as it is supposed to be "dirty". If you did clean that part of the intake within a few hundred miles of driving PCV gases will make it just as black as you see in the video.
What would be pitiful is after cleaning that part of the intake you dumped all of that crap in the bottom end of the engine.
@Thank you!! They kicked on at 225, just out of curiosity is that cooling fan circuit a pulldown circuit or pull up.. I figure sence the the ECM pull the relay to ground. Or am I all wrong about this..
Good mornig. What brand did you use? In my city I can only get the DORMAN. It's a good option? Thank you.
ScannerDanner hey rob,i have a astro 4.3 v6 cpi and it was bogging down like crazy to the point it will stall..so i put in a brand-new spider and its still doing the same exact thing! What thw hell can it be? I have replaced the map,iac,tps,all the plugs and wires etc...i start it,it starts right up and idles perfect,as so as i touch the gas pedal it boggs down and sputters and wants to stall..what else would make it do this? I feel like every part i replaced was for absolutely nothing because its still doing EXACTLY what its always done..fuel pump goes on for about 4/5 seconds i can hear it humming..i cleaned the egr..i need ur help with this one man please lol...its driving me crazy!! The vans all custom,interior,45 inch plazma tv,blueray dvd,22 inch rims,the things badass!! 92,000 original miles,one owner before me..new starter,belt,and everything else i named..it just kills me that its so mint and i cant figure out what else it can be..pisses me off! LOL..i put a new gasget when i did the spider too..made sure everything was all plugged in where it belongs..im stumped rob..what do u think it can be??? If u can send me ur number so i can send u some videos that be great.or i can text u.u have an email? Anything dude,i really need ur help.i know u can help me figure this one out.. ur the best ive seen on TH-cam by far!!! Great at what u do!! Thanks man,any help would be great!
Thanks,
David m, from Connecticut😀
@ScannerDanner Swtich inputs = pull-up or pull-down.
Output solenoids (relay in this case) = ground side switched or power side switched. It is easy to call this a pull-down design as the control wire voltage drops to ground when the relay is turned on. I just try to keep my students from calling it that so as to not confuse inputs and outputs.
for sure man. it's just a couple of rookies that have never seen the inside of an intake manifold before
One of those fuel lines broke on me and all of a sudden the motor just seized up.. I thought my batteries was dead cuz it wouldn’t crank so I called someone to give me a jump and still wouldn’t turn over so I started to take the spark plugs out and as soon as I pulled number 3 it started pouring out gas the cylinder had filled up with gas from that broken fuel line.. the reason I’m telling you is there is a lot of people out there that think there motor is blow cuz they think it’s seized up but really it’s just vapor locked..
for the scan tool your using. is that 95 blazer obd2? or obd1. I thought obd1 didn't have live data?
I will thumbs up & click on yours ads like I previously said to say thanks for taking your time & effort for making these videos.Thanks so much Dan,You rock!
truck starting perfect now, no long crank time. problem fixed. a little sluggish running rough at low rpm. any suggestions?? thank you
Great job. Lot of information. Really appreciate the whole video.
@CoolasIce2 Good point, but it isn't that common. I have only seen a pinhole in one of those 1 time.
I am working with a multimeter only not familiar how to check upstream. do I need a scanner to check. thank you very much
no, you can use your multimeter. It would be the black wire on the O2 sensor side of the connector that is your signal wire. Just remember it will only be rich DURING the acceleration period at wide open throttle. As soon as you let off the gas, the engine will decelerate and the ECM will shut down the injectors momentarily and it will go super lean. Super important test for us right now. I want to know if your bog is fuel related or not.
@scannerdanner Do you know what temp would kick on the fan on this 98 Buick century 3.1 I thought at 220f it should have kicked on live data showed 106 c that's about 220 if not more. So I poweprobe the fan it works checked fuse it's good. Power probe the relay it clicks. I'm starting to think ECM is not pulling relay to ground.
What did you charge for this? I have the same issue with the same truck. 1995 gmc jimmy. 4.3. I need his to be fixed.
Awesome video! doing work on my 1995 gmc jimmy, have done all the pressure tests, i'm going in. however, i have a question, Did you have to adjust pressure on fuel regulator? it has an torx screw inside for further adjusting, looking forward to your answer. and thank you in advance.
@ScannerDanner Oh, I had to shave the housing, that would be why.
I think I have a bad regulator because mine does the same; climbs to 62 psi then drops. While I'm in there replacing that, should I just replace the whole spider injector system too? My main concern is that I don't want to have that fail later on. Anything else you recommend doing while it's tore apart? Thanks a lot these videos will help a lot!
totally up to you. The rest of this assembly doesn't fail often. Yes, while it is apart. Pull the EGR valve and clean the intake passages.
@94vettelover2 No problem and thanks for the comment. Oh and my name is Paul, but I get Dan a lot :)
What scanner do you use for the obd1.5 I'm having trouble rfinding one
is that the oddball 94-95 model year cars that had an OBD2 16 pin but where not truly OBD2? Same scanner for an OBD1 with the 16 pin obd2 adapter
@FabricationStation36 Mostly students cars, but I do work for a few garages too. I am willing depending on what you have. Obviously my only interest is on the electrical side. Check engine lights, misfires, no starts etc. Also you can't rush me as educating my students comes first and fixing the car comes second. We can talk, go to my website and email me through there. My response will be from my home email address.
how is control the injector sincronize ontime with piston comprecion
It's me again Wayne with the 1994 s10 4x4. Chevy GMC 4.3 vortec vin number W. Put brand new spider in truck run fine it's been about month law kinda missing but I put everything new from icm rotor cap wires plugs put all that stuff on there before I fount out it was spider with fuel test was loosing pressure had about ,63 psi. Might have fowled plugs going to replace them they said gap was 45 but with vin W supposed to be at 60.. but yesterday I pulled up and it started smelling bad gas just out the blue done it twice just wondering if it's the TPS I hope spider and going bad ain't had it on a month got hesitation and little miss in it you can feel the miss when you go down the road but when you push gas throttle like it don't won't go nowhere found down the road you can push it but it don't kick down or even pick up speed I'm check timming to but it will fire right up these vortec never have another one
It does look like you could have changed the regulator without pulling the center out and pop injectors, is it possible ? Fantastic Vid. Looking forward to a vid on L&S term fuel trim functions.
When you say the CPI System fires all simultaneous; is this for all CPI Systems or just this application? Thanks!
@jgstang67 Wow, I am glad you feel that way, thank you so much for the comment!
@dreamvouyer67 thank you very much for the comment
got it, but it has to be later on the week were getting hit with a freeze and I do not have a garage I have been raising the van with a jack so its a slow process thanks again ill leave a comment when ready
@94vettelover2 Thanks but just click on the ads if you are truly interested. I believe your IP is tracked when you click so multiple clicks just inflate the numbers and then they take it away from me at the end of the month.
Hi there, Did you put silicon before to set the gasket?
No silicone needed. If you're having trouble with the gasket slipping, use a spray adhesive
@@ScannerDanner THANKS A LOT
thanks for the fast response (awesome) its a 1995 astro van 4.3 cpi changed fuel pump getting 55psi but when it warms up surges and when you snap the throttle it bogs down.
during the bog down snap throttle test, what is your fuel pressure? It should be about 60 psi during the rev up. Important that you are looking at the gauge DURING the increase in RPM because psi will drop as soon as you let off the throttle (normal)
Great video! Very informative, I learned a lot. I have a 96 2500 suburban with a 7.4l hard starting. I can see fuel seeping around the plenum gasket. So I know I have problems. More then usual poor fuel mileage. I didn't buy it for economy, but even still bad fuel mileage. Anyhow great video, I subscribed to your channel. Thanks again!
Replaced my regulator and solid psi now. Still having random shut off and wont restart. It does crank and i have spark in the distributor. Im thinking i need to replace the whole spider assembly with the new aftermarket electronic one because i have good pressure and a new fuel filter and want to avoid future issues with this faulty assembly. Would you agree or do you have any information for me to might help? TIA
+Andrew Love wiggle the two pin connector for the injector harness (blue and red wire). If it shuts down, pull the intake back off and tighten the injector terminals
I pulled my intake apart and checked for any leaking and loose connections. No leaks with the pump jumped and I have 59 psi while it is jumped. It drops to around 50 psi within 30 seconds and holds around there while slowly dropping. Could my fuel pump be failing?
It starts up with no issues on a cold start. While idle it is dying at around 10 minutes and then I cant restart it for a little while. Then it acts like its choking when I restart it. I have replaced the fuel regulator, fuel filter, spark plugs, and made sure I have spark. Also, my o2 sensor is working properly. This problem has been so sporadic and now my truck wont stay running at all. I'm sorry for bothering you. I am just trying to get my daily driver back up and running. TIA
What scan tool did you use?
I have a 1994 s10. It maintains 62 psi while cranking but won’t fire it will drop 8 psi in 10 minutes . But when i spray gas into the intake it will fire up and run for a second and cut off. Do you think the spider is bad or what else could it be.
You need to verify injector pulse. Disconnect the two wire (red and blue wire) connector and put a test light in between the two terminals (DONT LET THEM TOUCH EACH OTHER) and crank it and see if the light flickers on and off during cranking. My money is on that it does not.
I started to wiggle the connection to the injectors and it fired up, i could pull on the wires to make it run better or worse and finally got it where it runs perfect so i can get it to a better place to get a new connection. Thank you so much! My rig is fixed!!!
@@hunterharris37 If that is the case. It is not fixed. There is a connection inside of the manifold that goes right to the injector itself. Those terminals need tightened up. You'll have to pull the upper intake to fix it.
Having more issues and figured i would come back to you! When i jump the fuel pump i get a constant 60 psi. As soon as i turn the pump off it drops immediately to 10psi. I have tried to isolate the fuel pump and the return line and i can’t find where it’s bleeding off. I replaced the fuel pump and the pressure regulator but not the whole CPI unit. Rig is running really sluggish and long hard starts. Any other advice?
@ScannerDanner You are most welcome .
great vid mr Danner, i wrap a few cloth's around fuel lines when i disconnect them.
it catches any spray out ;)
Glad u said they all fire at the same time nobody else said anything about that. Also anyone know I found rtv around the the electrical connector did it come like that
@fivefortyeye540i sorry I didn't respond sooner, I've been very busy. I am glad you found the problem
Shit, man - you know your stuff. And a natural communicator. Yey!.
Thank you!
well, I respect your opinion for me that guy is a genius. I have learned a lot diagnosis Technic and I have decrease my math jajjaaj. how wonderful day I absorb good things and this guy is providing 99% good info and 1% on this vehicle not cleaning there ho well it proves nobody is perfect.
Great vid, but since the nylon fuel lines are known to go bad, why didn't they get replaced? They're only $40. DORMAN Part # 55163
what if the pressure does not rise when snapping the throttle.
Is it a CPI system like this one? Some cars, that is normal as the regulator is in the tank (one set psi)
whats wrong if my fuel pressure is at 75psi? I have a 95 blazer s-10 4.3... same engine.
Faulty regulator or restricted return line. Remove return line and install a new temporary line and run it into a gas can. Recheck psi. If still high, change regulator, if now normal, find the kink in your return line
thank you for your help brother. If you have any computer problems i would love to help you out in return! God bless you, fight the good fight
Can you do a video on replacing those fuel lines running to the spider?
sorry man, won't be seeing one of these any time soon. They are all rotted out from rust
ScannerDanner: for someone with quite a bit of time under the hood with DIY mechanic projects, how long would you estimate it would take to get everything loosened, disconnected, etc, and the the air intake plenum off? I've never taken one off.
Also, does the plenum gasket need to be replaced every time the plenum gets pulled off? For example, say I opt to just buy the inlet/outlet lines, and the fuel pressure regulator, take it all apart and find out the injector assembly hoses are cracked and need to be changed. If I put it back together with the new gasket (and the other two new parts) can I drive it around while I wait for the spider assembly to come, and not worry about buying another gasket.
I'd rather not dish out the money to buy the assembly if I don't have to, but don't want to get everything apart and find out I have to order a spider assembly and have to wait with a completely non functional car, and on top of it buy another new gasket.
Hope that last question made sense. Would it just be worth it to buy everything together and replace it all since I'm in there, all at the same time?
Thanks!
It is not a hard job at all and it is no big deal to go back in if you have too. And I have re-used the gasket, but not the original one. We had a new reg. leak and had to go back in 2 days later.
Thanks for the reply, Scanner Danner. I put a fuel pressure gauge on, ~62 at key on, held for more than 20min within at 62psi (is it possible it could have been held open/close). I turned it on and opened the throttle, it would go up to about 65 than drop to about 57ish after letting throttle close. By that time I had already bought the fuel pressure reg. and a gasket. I dicided to just pull the plenum off and worse case if nothing was washed, I'd just swap the gasket. Regulator side was all washed with pools of gas. Inlet side was pretty dry and black. I keyed on, and nothing leaked. I swapped out the FP Reg, leak tested, keyed-on, pressure dropped from 62 to 58ish after that, but stayed at 58 for a long time.
I put everything back together and it seemed to be running a bit better, but as soon as I stop at a red light, do a right on red and then go to accelerate, it starts missing and sputtering (right around 20-30mph) acting like it wants to stall. In park, it's fine. I have new plugs (Cyl 2 was completely burned up: no electrodes -that may be from bad threads as it is hard to hand tighten) cyl 4 and 6 were caked (2 4 6 are on regulator side) 1, 3, 5 were clean; new fuel filter (old one I couldn't hardly blow through), new ignition control module (old one was arcing); PCV valve rattles and I cleaned that out a bit with some cleaner.
I"m not really sure what else it could be.
Sorry that was a long reply, but you caught me right after washing the grease and manifold soot off. :)
Thanks again!
wiggle the wiring harness where it goes into the intake. Should be a red and blue wire. This connects to the injector inside of the intake. If the engine stumbles when you wiggle these wires, the connector is lose on your injector. (common issue)
Great, Thanks! Thanks for posting such great and informative videos, btw.
Bart Black
I wanted to follow up after all my car problems got resolved. I did a lot of reading and research via youtube, forums, etc: I finally got my hands on a multimeter and went through and tested EGR valve, TPS sensor, IAC valve, and MAF sensor. Everything was as should be and I couldn't figure out why my car was still wanting to stall out during acceleration. I finally got fed up with it and took it to a mechanic yesterday. He was impressed with the list of things I had tested and/or replaced. It turned out that the distributor cap, the rotor, and the spark plug wires were corroded, burned up and barely producing any spark. And the Distributor itself was rusting. In my defense, the items I replaced did need it (ex-clogged and old fuel filter).
About a month prior to my problems starting, I had purchased a set of spark plug cables with the ignition control module. For the last 2 weeks I've been thinking, "Maybe I should pull the wires and replace them with the ones I just bought." But the first mechanic had told me that the car was producing great spark and that the wires didn't look like they needed replacing. I don't know if he actually ever checked them.
I'm a bit embarrassed that I did all this diagnostic work, and never pulled the distributor cap or the cap-end of the wires. I based it on the 1st mechanic and never confirmed what he told me. Luckily replacing the cap and the rotor and the wires solved the problem, without replacing the distributor.
I guess the point is, my dad always said "start with the simplest, most basic, and cheapest part to replace, and work your way through to the more complex parts, because a lot of times it could just be a loose wire or a blown fuse." HE was right! For all those DYIers, don't under estimate the basics, and verify for yourself what someone may have told you.
I could have had this problem fixed 2 weeks ago. Anyways. Carry on!
@ScannerDanner I wanted to include more of my symptoms and what i did to resolve them , but we are only allowed to load so much text here .
@1elAguila thank you too my friend
This is good
This almost looks like my 95 gmc jimmy 4.3l v6 vortec. I wanna try the fuel pressure test as well.
What ? they fire at the same time? so it wastes gas and injects it at wrong times on some of the cylinders? Another reason to use the upgrade injector system. I know the new system has actual injectors where the poppet valves go, it makes me wonder how the new system can have individual injectors open if system was designed to give electrical signalling for all to open. I'm a little skeptical of your claim actually but I realize this is th eolder system with that aluminum intake manifold, so maybe it doesnt apply
Intake valve openings are the key to understanding how and why this system can work. There are other injection systems that have one driver for the entire engine. These are called group fired injection systems. This is no different, they just figured out how to do it with one electrical injector.
I can't thank you enough Paul. YAH bless you brother.
the line to the cylinders went on top of the fuel pressure and return line.
in a 2001 astro how hard is it to get to the fpr could an average Joe take it apart
Absolutely. It's not a hard job at all
great video very informative thank you
Yep!! It's good and clogged my guess it had missfire and was ignored and plugged the cat.. That's what I get for not having confidence in what I have learned from ur teachings..
Just this design. Newer styles than this one where fired sequentially. (1996 and up)
I believe I got to 5 or 600. not very sure since meter kind of going up and down. ill have to double check again didn't check my voltage from the ecm. ill try to get a better reading thanks again.
yeah, a voltmeter is a little slow to update, was that on a dead rev in park or were you test driving it? My suggestion would be to rig up a jumper wire to the O2 signal wire and then run it inside the truck and take it for a test drive. This will allow you to hold it at WOT for a longer period of time than what a dead rev would allow, giving your meter a chance to update and give us a true picture of what is going on.
Of course the alternative would be to use scan data if you have one that will give you O2 mv
great video very informative nice job amigo
keep up the good work.
Great video, thanks a lot for all the work!
Silly design. These engineers must think it's pretty funny putting the regulator in such a stupid spot. I'd simply change mine in 5 mins with a used one IF it was a 'normal' design... guess it'll stay the way it is. After gas prices jump up more I'm sure many of these gas suckers will be retired anyway like mine will be in the Spring... it has 362k on it anyway.
Good vid.
Awesome thanks!
Thx bro 👍💪
@ mike williams seems like this video is not for you
thanks for the video .!! (GREAT Video)
Thanx
No problem
Thank you
Both are sticking rich at idle
Killer!
Btw sold Buick today
Block egr off to save rubber, slap it back in for emissions when needed. piss poor design.
So you said that the injectors shoot out all at the same time so that means that is a lot of fuel wasted instead of saving fuel with this system so the Chevy engineers are a piece of crap, I have an 02' Chevy Astro van and I've seen that the fuel pressure regulator is inside and I just got really angry that the part is inside the plenum this is a PIECE OF SHIT I will never buy another Chevy
Interesting that you are teaching students how to do repairs, yet you make excuses for not cleaning up components & surfaces!
Nothing like an educated "hack"!
Pitiful!