Many years ago when I was at the GM training center the instructor constantly told us to "think" like a computer when diagnosing drivability concerns. Good advice that has served me well
I wonder how many of us even guessed that an ignition coil problem could be the culprit for an input/output transmission shaft speed code. I certainly didn't and furthermore, doubt any flow chart would suggest such a possibility either... Another masterclass by Bernie.
My main question is with that ignition problem why is it only as affecting the speed sensor circuits and not other circuits such as the crank or Cam having induced voltage spikes well that has to be bleeding back through the computer at this point from what I see to only affect the speed sensor that doesn't sound logical to me
Hey Mr Thompson, I love your content and can’t wait for each video you produce. Being bothered to share your knowledge with us wannabe expert diagnostic techs is very much appreciated and long May it continue. Thank you!
Mr Thompson I wanna thank you for taking the time to produce these case study videos. The amount of information passed on to the audience is invaluable in building a stronger diagnostic foundation
Really informative video. I love "the test drives the diagnosis" approach it saves so much time and is extremely accurate. This was a masterclass on how to use measurements to look at the car from a completely different perspective. Very well done!
Exact same excursion with the same problem. Just bought some of that 505 crf. Also the oil treatment. Not cheap but Scotty Kilmer also reviewed the oil treatment with and noticeable difference in engine noise afterwards. Thanks!
I was driving to Florida few years ago with my 03 Ex 6.8 176K , was running rough and getting the flashing code on the shifter. Sargeant Service Center in St Augustine diagnosed as coil pack failure. I was 1000 miles from home and they could have pulled my pants down. Credit to that shop. Changed plugs and coil packs, I didnt have any problems the 1000 miles home. Now sitting pretty at 215K. I always have used Dextron, will try the 505.
@@philh9238 Ivan is unsure on a lot of things but eventually comes to a conclusion. Has had misdiags in some of his videos and that just shows that some cars are just too hard to hit the nail on the head. Bernie knows too much to misdiagnose since he knows technical information that a lot of us dont. He is an engineer.
@@mejesse809 Ivan can't hold a candle ? This is rude. Ivan is the same level as Keith. Bernie Thompson is the guru. Stuzman is also engineer and knows the finicky things about electrical and electronics but not everyday mechanic. Maic Salazar has lab where he REPAIRS modules of european vehicles. Can't hold a candle.. bad comment..really bad 👎
Had an older f150 years ago, coworker did plugs, coils, injectors and the truck would still break up, "miss" and stall. Ended up being a faulty speed sensor in the rear diff causing speed limiter to kick in. Was a fun diagnosis
I bought the escan in 2006 and the escope limited with transducers a couple years later. I wish he had all these videos back then. Sure would have been easier to learn to use them.
Bernie really has a Hand for the strangest Cars.....If he would not film it, many People just could not imagine the Problem and the Cause and the Fix.....CRAZY.....
defiantly learned something with this video great Job. After the coil was replaced you kept saying the the firing line was showing a lean condition wish you would have shown the fuel trims and/or fuel pressure.
Anyone this skilled or have these skills in West Yorkshire, UK? If so I'd love to come and volunteer with you on a Saturday. I've been a mechanic for 20 years in a garage that isn't interested in this kind of stuff and I'm craving some knowledge! Awesome video and diagnosis 😊
Bernie, where can I go to learn about how to determine a scope readings shape? Like when you say "that looks like a carbon arc, or a coil on a lean cylinder" I'm a dealer tech and have never been taught anything like this, it's astounding how in depth they are.
I'm very curious why a cylinder balance test wasn't performed and I also remember you saying in the beginning that all the fuel trims look fine usually if there's some type of a misfire and fuel trims will start to go in a lean direction?
Regarding "clogged injectors", I'm curious what fuel trims and WOT O2 looked like. Also, injector drop test might be interesting, especially before and after fuel additive.
Can you mention what sae books you recommend? Thanks i learn alot from you and one day i will afford to buy elite scope. I will become like you one day.
great diag and good to see the proof on the injector cleaner. with 200k all the coils and plugs have been stressed. although its fixed a recomendation for a full set of plugs and coils would be offered. i really didnt like the looks on #1
hola sr thompson agradesco mucho sus videos he aprendido mucho de ellos gracias. tengo problemas con una jeep grand cherokee 4.7 2001 se sobrecalienta y no he encontrado buena informacion sobre hidro cooling fan de como funciona y como diagnosticarlo gracias de antemano por su tiempo y que dios loi bendiga por ayudar a tanta gente
Great diag as always, Autel maxisys greatest choice:) I can't afford high end oscilloscope yet, terrible times coming.. Hantek doing some job but rubbish resolution..
I also will perform a lot of tests and similar circuits or the same ones which is the key on engine off determine whether or not there is actually a problem inside the PCM
Bernie, if you read these comments, can you expound on how the computer’s assuming transmission slipping when the output is showing higher rpm than the input? It should be the other way around if it was a slip detection strategy. I think this was purely an EMI concern from a misfire and the computer losing counts than it was a fuel cut strategy from a slip (which it didn’t have at all)
Was thinking the same thing…had a older gm car do this due to the wiring harness for the output shaft speed sensor intermittently grounding against the case. Guess the bias voltage and the short to ground was enough to create current flow and when the short would go away it would spike a little bit like an ignition coil which caused the computer to interpret the high spikes as a speed signal. Just as you were coming to a stop it would shut off. Seemed to me like it was going into open loop/fuel cut since its saw a speed signal with no throttle input like if u let off the gas while coasting at say 50mph, the computer would turn off the injectors until you got back into the throttle. Still always impressed with Bernie’s knowledge and the tests he comes up with. Also grateful he’s willing to share it.
When you replace spark plugs you replace all of them, would it not be a good idea to just replace all injectors or coils, so you dont have it come back for each one that fails?
You mentioned understanding what the computer does well you would have to be privy to that information otherwise it's just guess work every manufacturer uses a different format to accomplish sometimes the same thing also I'm curious on how the ignition is only affecting the speed sensor and nothing else if that be the case then there must be something wrong with the PCM allowing it to infect the speed sensor circuit and nothing else
We had 2002 through 2004 F250 through F550's some with the 5.4 V8 and 6.8 V10 engines. We also had some E250 and E350 vans. The E350's had the 6.8 V10's. I would see many of the F350/6.8 V10's have one specific computer code for the I.S.S. or Input Shaft Speed sensor in the transmission. The first one I got drove me crazy because no matter how I tested the vehicle, the code would not return. All I had for a scope between 1995 and 2016 was my Fluke 98 Series 2. I sure wish I had my Pico back then. One day reading some iATN postings, a tech indicated how he had a V6 minivan with intermittent engine stalling and he found out by putting the vehicle inside the shop, wetting down the V6's spark plug wires then starting it, number 1 was arcing along the length of the wire and the engine would stall. The wires were original and the vehicle was old, so new(very much needed) ignition wires and worn with a large gap plugs were replaced. No more stalling and a better running vehicle. So I decided to check the plugs and sure enough......W I D E gaps on all 10. The coils were original and Ford had updated their Motorcraft coil after a few years. After properly gapping and torqueing the plugs then replacing the 10 coils, no more I.S.S. computer code. The F350's were utility body duel rear tires and we're loaded down with tools and parts. These were L.A. Depth of Water & Power trucks with 25,000 to 40,000 miles on them when the problem would occur. City stop and go mostly, so plug wear was normal. The F250 pickups had a similar problem but they had over 50,000 miles on their odometers. Your video suddenly made sense why I saw those vehicles with the I.S.S. code. Seeing the "Ignition Strike" backing up into the sensor which shut off the engine made sense! That strike also helped to create the carbon tracking internal to the coil. I'll bet the spark plugs had worn and wide gaps. Ignition coils don't normally like wide plug gaps! Thank you for this video!
my brother said his f-150 trans was acting up. 130k i asked him when he changed the spark plugs. he hadnt cuz he heard the 5.4 nightmares. besides he said it ran ok. plug change fixed it. these things are engineered on the edge. everything is interwoven.
As a brother advice do not throw your money away by buying their worthless scanner, I wish I didnt buy it from them, it was the first mistake which I made in my life I regret for that be aware not to do so I warned you just for sake of God.
This man could work for NASA. His way of handling that scope is rocket science for me.
his partner is literally a rocket scientist so...
Many years ago when I was at the GM training center the instructor constantly told us to "think" like a computer when diagnosing drivability concerns.
Good advice that has served me well
I wonder how many of us even guessed that an ignition coil problem could be the culprit for an input/output transmission shaft speed code. I certainly didn't and furthermore, doubt any flow chart would suggest such a possibility either...
Another masterclass by Bernie.
Oh yea imagine following a flow chart for this.
Replace sensor: check resistance on wires, replace PCM
My main question is with that ignition problem why is it only as affecting the speed sensor circuits and not other circuits such as the crank or Cam having induced voltage spikes well that has to be bleeding back through the computer at this point from what I see to only affect the speed sensor that doesn't sound logical to me
Hey Mr Thompson, I love your content and can’t wait for each video you produce. Being bothered to share your knowledge with us wannabe expert diagnostic techs is very much appreciated and long May it continue. Thank you!
Love the amp clamp trick! Thank you Bernie for another great diag and lesson 👍
Bernie is just on a whole different level. Always amazed
Always a good day when he post a video
Mr Thompson I wanna thank you for taking the time to produce these case study videos. The amount of information passed on to the audience is invaluable in building a stronger diagnostic foundation
Thank you Mr Thompson. Your knowledge is so valuable. Thank you for sharing your experience. I appreciate all of your videos.
Nice job! Thanks for all you do for the technician community.
Thank you , knowledge and experience is always better than chance
Really informative video. I love "the test drives the diagnosis" approach it saves so much time and is extremely accurate. This was a masterclass on how to use measurements to look at the car from a completely different perspective. Very well done!
Exact same excursion with the same problem. Just bought some of that 505 crf. Also the oil treatment. Not cheap but Scotty Kilmer also reviewed the oil treatment with and noticeable difference in engine noise afterwards. Thanks!
I was driving to Florida few years ago with my 03 Ex 6.8 176K , was running rough and getting the flashing code on the shifter. Sargeant Service Center in St Augustine diagnosed as coil pack failure. I was 1000 miles from home and they could have pulled my pants down. Credit to that shop. Changed plugs and coil packs, I didnt have any problems the 1000 miles home. Now sitting pretty at 215K. I always have used Dextron, will try the 505.
" I was a 1,000 Miles from Home & they coulda pulled my Pants down " ( if they
wanted too - but they were honest & sharp ) !
Don't stop pumping them out Bernie 👍😎
This guy is HANDS DOWN the best. These guys aren’t everywhere! Ivan at Pine Hollow is pretty damn good as well!
Agreed. Don't forget Eric @ South Main Auto Repair
Ivan can't hold a candle to this guy, there's only one guy I've seen as good as Bernie, Keith at New Level Auto...
Idk Ivan is pretty sharp. I’d place my money on him figuring out the same cars Bernie does
@@philh9238 Ivan is unsure on a lot of things but eventually comes to a conclusion. Has had misdiags in some of his videos and that just shows that some cars are just too hard to hit the nail on the head. Bernie knows too much to misdiagnose since he knows technical information that a lot of us dont. He is an engineer.
@@mejesse809 Ivan can't hold a candle ? This is rude. Ivan is the same level as Keith. Bernie Thompson is the guru. Stuzman is also engineer and knows the finicky things about electrical and electronics but not everyday mechanic. Maic Salazar has lab where he REPAIRS modules of european vehicles. Can't hold a candle.. bad comment..really bad 👎
What a wealth of knowledge! I love watching this guy work!
Had an older f150 years ago, coworker did plugs, coils, injectors and the truck would still break up, "miss" and stall. Ended up being a faulty speed sensor in the rear diff causing speed limiter to kick in. Was a fun diagnosis
I wish i could sit with bernie and have a one on one class i feel like you would leave with so much knowledge
I bought the escan in 2006 and the escope limited with transducers a couple years later. I wish he had all these videos back then. Sure would have been easier to learn to use them.
Wow you've no doubt been doing this a good while. I'm dealing with the same thing on a 02 super duty 6.8L
I’m always waiting for you ? Mr Thompson. Thank you for always great videos.
Incredible diagnostic skills!!!
Bernie Thompson , my Man ,MyMainMan "Heavy-Hitter " outta
Albuquerque , New Mexico !
Bernie really has a Hand for the strangest Cars.....If he would not film it, many People just could not imagine the Problem and the Cause and the Fix.....CRAZY.....
Cars with strange problems are quite common; you might know them as AUCTION CARS and TRADE-INS 😆.
defiantly learned something with this video great Job. After the coil was replaced you kept saying the the firing line was showing a lean condition wish you would have shown the fuel trims and/or fuel pressure.
Anyone this skilled or have these skills in West Yorkshire, UK? If so I'd love to come and volunteer with you on a Saturday. I've been a mechanic for 20 years in a garage that isn't interested in this kind of stuff and I'm craving some knowledge! Awesome video and diagnosis 😊
Fascinating stuff, so much to learn.
im not going to freak out right now...Love you Bernie, if you did ever freak out Bernie, i would just pack up and go home.
Bernie, where can I go to learn about how to determine a scope readings shape? Like when you say "that looks like a carbon arc, or a coil on a lean cylinder" I'm a dealer tech and have never been taught anything like this, it's astounding how in depth they are.
I'm very curious why a cylinder balance test wasn't performed and I also remember you saying in the beginning that all the fuel trims look fine usually if there's some type of a misfire and fuel trims will start to go in a lean direction?
awesome video ..Master technician for sure
thanks Mr Thomson
Regarding "clogged injectors", I'm curious what fuel trims and WOT O2 looked like. Also, injector drop test might be interesting, especially before and after fuel additive.
Fordtechmakuloco said he has never seen clogged injectors with the additives in todays fuel..
Can you mention what sae books you recommend? Thanks i learn alot from you and one day i will afford to buy elite scope. I will become like you one day.
great diag and good to see the proof on the injector cleaner. with 200k all the coils and plugs have been stressed. although its fixed a recomendation for a full set of plugs and coils would be offered. i really didnt like the looks on #1
Great diagnosis. Can you recommend a book or books where such knowledge can be learn. Maybe you can write a book
hola sr thompson agradesco mucho sus videos he aprendido mucho de ellos gracias. tengo problemas con una jeep grand cherokee 4.7 2001 se sobrecalienta y no he encontrado buena informacion sobre hidro cooling fan de como funciona y como diagnosticarlo gracias de antemano por su tiempo y que dios loi bendiga por ayudar a tanta gente
Great diag as always, Autel maxisys greatest choice:) I can't afford high end oscilloscope yet, terrible times coming.. Hantek doing some job but rubbish resolution..
Awesome case!!!
I also will perform a lot of tests and similar circuits or the same ones which is the key on engine off determine whether or not there is actually a problem inside the PCM
Great job Mr.thompson.
Thanks Bernie!
Bernie, if you read these comments, can you expound on how the computer’s assuming transmission slipping when the output is showing higher rpm than the input? It should be the other way around if it was a slip detection strategy. I think this was purely an EMI concern from a misfire and the computer losing counts than it was a fuel cut strategy from a slip (which it didn’t have at all)
Would one mot assume in that case it would also loose the spark aswell? The factor it only looses injector indicates its some fuel cut strategy imo
Was thinking the same thing…had a older gm car do this due to the wiring harness for the output shaft speed sensor intermittently grounding against the case. Guess the bias voltage and the short to ground was enough to create current flow and when the short would go away it would spike a little bit like an ignition coil which caused the computer to interpret the high spikes as a speed signal. Just as you were coming to a stop it would shut off. Seemed to me like it was going into open loop/fuel cut since its saw a speed signal with no throttle input like if u let off the gas while coasting at say 50mph, the computer would turn off the injectors until you got back into the throttle. Still always impressed with Bernie’s knowledge and the tests he comes up with. Also grateful he’s willing to share it.
I believe it is an overspeed condition so the injectors are being cut to reduce speed.
When you replace spark plugs you replace all of them, would it not be a good idea to just replace all injectors or coils, so you dont have it come back for each one that fails?
Not on these. You run the chance of stripping out the plug threads in the head. It's best to take the if it's not broke don't fix it approach to this.
I have the same code on my Mercedes Benz. will follow the steps you use.
Amazing diagnosis!!! 👏 😎
hi Mr. Thompson. thank you for sharing your experience
do you recommend me ALL DATA or ONDEMAD (Mitchell)
Well what happened to the speed sensor? Im sorry but you said at first ot was a safty cut off to protect transmission?
Thanks again master.
Like it it's was very clear understanding
This vehicle doesn’t pass by the fuel station very often..
You mentioned understanding what the computer does well you would have to be privy to that information otherwise it's just guess work every manufacturer uses a different format to accomplish sometimes the same thing also I'm curious on how the ignition is only affecting the speed sensor and nothing else if that be the case then there must be something wrong with the PCM allowing it to infect the speed sensor circuit and nothing else
How come we don't get to see the speed sensor signal again after all that's changed to verify that that problem has disappeared
I can see where someone would throw a lot of parts at it
We had 2002 through 2004 F250 through F550's some with the 5.4 V8 and 6.8 V10 engines.
We also had some E250 and E350 vans. The E350's had the 6.8 V10's.
I would see many of the F350/6.8 V10's have one specific computer code for the I.S.S. or Input Shaft Speed sensor in the transmission.
The first one I got drove me crazy because no matter how I tested the vehicle, the code would not return.
All I had for a scope between 1995 and 2016 was my Fluke 98 Series 2.
I sure wish I had my Pico back then.
One day reading some iATN postings, a tech indicated how he had a V6 minivan with intermittent engine stalling and he found out by putting the vehicle inside the shop, wetting down the V6's spark plug wires then starting it, number 1 was arcing along the length of the wire and the engine would stall. The wires were original and the vehicle was old, so new(very much needed) ignition wires and worn with a large gap plugs were replaced. No more stalling and a better running vehicle.
So I decided to check the plugs and sure enough......W I D E gaps on all 10. The coils were original and Ford had updated their Motorcraft coil after a few years. After properly gapping and torqueing the plugs then replacing the 10 coils, no more I.S.S. computer code.
The F350's were utility body duel rear tires and we're loaded down with tools and parts.
These were L.A. Depth of Water & Power trucks with 25,000 to 40,000 miles on them when the problem would occur. City stop and go mostly, so plug wear was normal.
The F250 pickups had a similar problem but they had over 50,000 miles on their odometers.
Your video suddenly made sense why I saw those vehicles with the
I.S.S. code. Seeing the "Ignition Strike" backing up into the sensor which shut off the engine made sense! That strike also helped to create the carbon tracking internal to the coil. I'll bet the spark plugs had worn and wide gaps. Ignition coils don't normally like wide plug gaps!
Thank you for this video!
what diagnostic tool are you using?
A " 4 " or " 8 " Channel
ATS ' Scope , found @
HeadQuarters
www.automotivetestsolutions.com and here in
California @ www.aeswave.com
What’s books would one read?
Blessings 🙏
I had bad a couple bad injectors on my 7.3 i didnt replace only the bad ones i removed all and restored them
The 🐐
Perfect.
My Zeus can't get these results.lmao
I want these results in my bay as well.
YES!
Bad software allowing engine speeds below the idle speed, they should know the vehicle speed is 0, from the abs unit.
my brother said his f-150 trans was acting up. 130k i asked him when he changed the spark plugs. he hadnt cuz he heard the 5.4 nightmares. besides he said it ran ok. plug change fixed it. these things are engineered on the edge. everything is interwoven.
💌🐑 Bernie
As a brother advice do not throw your money away by buying their worthless scanner, I wish I didnt buy it from them, it was the first mistake which I made in my life I regret for that be aware not to do so I warned you just for sake of God.
bla bla bla ,,,,,,, how much does it cost and and can it be fixed soon . he wants to charge 130x hour to touch a screen for 1 hour . rediculous.
Your forgetting the 20k investment in tools and your also paying for the decades of knowledge.