The XTREME Parts Cannon! (GM Chevy S10 P0300...FALSE Misfires?) 

One of hardest things to explain to customers is that new and good have 2 different definitions

I’m not surprised that a cheap crankshaft position sensor caused this issue. What I do find surprising is that all of the other Amazon/aftermarket parts that have been thrown at this truck worked properly and didn’t contribute to the problem. As far as the cooling fan pushing air rather than pulling it, nice catch Ivan, some people just shouldn’t be allowed near hand tools.

I'm always amazed with your fixes. Coming behind others to solve an original problem is nerve racking.

Ivan, I think I just learned what happened to a customers car that I could not diagnose. 3 series BMW 325i 2001. This one has haunted me. I would get a cylinder 6 misfire, ecm would disable the injector determining it was catalyst damaging. Did compression checks while cranking and while running to check for valve float or something weird. Checked okay comparable to other non missing cylinders. Swapped coils, no change. Spark plugs were autolites, and i had the customer approve putting in oem Bosch twin electrode plugs. No change. Ordered in a fuel injector as a last resort and numbers matched the injector calibration and had to call it. Couldn't diagnose it. Plugs were wrong, and the only part i fired at it as a last resort was the injector. I didn't own a scope at the time, and didn't know how to use one (until i bought one because of you lol). I did harness checks, i tested and inspected everything i could only firing the parts cannon as a last resort with that injector. Since I didn't see a code for the camshaft or crank position sensors, I assumed they were okay. And the WILDEST PART THAT I KNOW WHY NOW BECAUSE OF YOU! If I cleared the codes while the engine was running, it ran like glass for 8 seconds, perfectly, then would detect that misfire and cut the fuel to that cylinder. This guy had 4 other mechanics look at it, not knowing what the others had done and i dove in. I refused to replace parts that i couldn't prove were bad. The only variable was what I couldn't see on the injector while it was operating. This truck running great even with the code on, just like the bmw did after i cleared the code, i would adjust bet the cmp or cank sensor was a crap box store unit. I always use bosch parts on motronic systems, learned that lesson too many times. Where I was wrong was assuming a part was working properly when though it may not have. Seeing how that ecm picked up on certain cylinders only, just got the bmw did, oh that has to be it!!!! I never charged the customer for the diagnosis and only charged the parts cost for the plugs. I told him if I can't figure it out, I'm not charging you. That car has been the only vehicle i haven't been able to diagnose in my career. I wish my customers car didnt burn down now lol. Another mechanic after me left the + lead from the battery disconnected while pulling the intake manifold (guess the guy thought it had a manifold leak even though I smoked it before him) and the positive cable touched ground and lit up the car. I'll never be able to find out if that car has the same issue as this truck, but I'm so sure of it now!!! Thank you Ivan! I'm going to sleep better tonight 😂

When i asked on Jimmys (Master Mechanic) YT channel " Jimmy making it work " who would he trust to work on his own vehicle, your name came up first, quite some recommendation 😁

Superb diagnostic job. Excellent explanations. Coincidentally, our buddy Eric O. concurrently had a similar case study. Both of you guys deserve Mechanics of the year awards!

I have never used the duty cycle conversion in Picoscope, but you bet your butt I'm gonna now... Thanks, Ivan. You make us all better techs!

Eric O @SMA did a great video today using his scope to diagnose a fault he has never seen that 2 other shos couldn't fix. You guys are the best.

Thanks Ivan. I always knew the CPK was used to check for misfires, but I never knew it was so sensitive. The waveforms show just how small of a deviation the computer is looking for.

Brilliant way to confirm. I have used math channel with frequency to flush out bad tone rings on ABS. Never though to use duty cycle, but I will add it to my routine. Thanks and keep up the good work!

Nice find, so used to crankshaft variation relearn and AC Delco distributor cap fixing 99% of the P0300 issues!

Oh boy. and I am sure that loose/cheap mounting bracket made the pulses worse. Wow! I figured out the fan issue as soon as I heard them turn on with the ignition. I am shouting at Ivan to put his hand in front of the grille to determine direction of flow. Hahaha. 👍😎👍

The bonus footage is great on this one. I wish I knew how to use the Math features better with my scope.

The temptation to use less expensive aftermarket parts is great, especially when the price difference is enormous and you have little money. If you must buy OEM parts, the best way to do it is look for the cheapest source online and then see if you can get a local dealer to match the price. I have found many are quite cooperative and you don't have to deal with waiting or returns if there is an issue. Developing a relationship with the local dealer parts guy can be a great time and money saver.

Extremely fun to watch as an owner of a 98 Blazer! I've had to clean the crank position sensor connector but the original oem is still doing its job!

I just don’t understand why some people forge ahead in complete ignorance. If you don’t know what you’re doing, find someone who does. Excellent video! Genius on the duty cycle graph!

That was amazing! Like you said, "The power of the (Pico) scope." I remember those OEM distributors had a small amount you could move them to readjust the cam to crank offset due to timing chain wear. If you removed the distributor you could file the opening of the adjuster slot and that would give you more adjustment. If you zeroed it out and the engine ran poorly or stalled, it was diagnostic time possibly a stretched timing chain. Had several mini vans in the fleet that had these 4.3 V6 engines. They were like pocket rockets! A light van with a strong engine. Remember, these 4.3L V6 engines were "The GM 5.7L V8 with the back 2 cylinders cut off" so we were told. The weak link in the early ones was the "spider" fuel injection system. The updated one worked GREAT! Good one Ivan!

Hi Ivan, as far as the overheating I remember that all the GM's of that time needed their new coolant installed with a vacuum filler other wise there would be an air block within the engine that causes overheating problems that appeared like a blown head gasket. it appears that the owner tried to mitigate this with the fans. Rich

Always amazed at how smart you are and how not smart I am. BUT i always love your vids!!!!

Wow! fantastic diagnosis and the reasons for the fault. I would never had suspected, that a shift in duty cycle would have mattered that much, but it did. Brilliant.

The variation in duty cycle is likely the physical distance changing, ie the sensor bouncing in & out. Great fix as usual Ivan.

This diagnostic encompassed a wide range of knowledge and expertise. This one reminds me of a similar situation, a looong time ago, where a mag sensor was *glued onto the magnesium housing of a gas turbine. Naturally, it vibrated loose, ever so slightly and just enough to cause random 'no light-offs'. It drove us nuts and nearly sent us into parts cannon mode. Enjoyed watching you nail this one. Miller time :-]

I would have suspected something looking at the frequency on the bad one compared to known good. Great video and use of the scope.

Nice video. This one is worthy of the Staten Island Express. Great to learn about the duty cycle with the scope. Thanks so much Ivan! I was wondering about the fans. So was happy to see the bonus bonus footage!!!

Wow really cool with the graphing duty cycle. I never thought to try that out! I had a Honda with an after-market sensor that I couldn't find a diff. I'm going to check with a math channel to have some closure! Thanks for sharing!

"Diagnostics isn't cheap, but it's guaranteed." Thanks Ivan!

Nice Job! I've had a few oem 4.3 crank sensors hitting the reluctor which really pisses off the PCM! Gm actually had shims available back in the day. I always try the re-learn 1st on miss fires I can't feel ESPECIALLY on 6.0 C/K

Excellent work as always Ivan!! That crank sensor problem is real subtle! Great catch on the fan motors too.

Awesome ‘scope explanation. Fans hooked up backwards - submit to Just Rolled In.

Holy crap, that variation in the cheap crank sensor was so tiny!! That's insane! Learned so much from one tiny glitch. :D

And why I refuse to use Junk from ebay and Amazon, especially any sensor and FAKE Denso parts, Absolutely rock solid work, Looks like I need a Scope and learn how to use it like this if I want to be successfull repairing any Modern machinery in the Future. Thanks for Great Content like this.

Great info I think a lot of us learned on that one. Thanks Ivan for always inviting us in your shop. PS set the parking brake before turning ignition on for headlights to stay off on a GM vehicle

Another great diag! The cooling fans fix was hysterical. That was one for that Just Rolled In site.

Bernie level diagnosis and explanation. Nice.

Ivan, AWESOME as always ur approach always amaze me thanks for sharing.

Absolutely love the duty cycle analysis.

It's surprising how a 0.5 millisecond change in duty cycle can affect misfire counts. The moral of the story is don't buy cheap parts for critical engine monitoring functions. Thanks, Ivan.

Ivan, love the cooling fan fix. The rest of this video pretty good as well. Thanks for Sharing!

Opposing fans - good Band Name for mechanics.... great ep and great scope analysis. Thanks Ivan.

Very very detailed and deep diagnosis and explanation 👌 👏 loved it new to my knowledge cabinet.and again you remind people no aftermarket junk always oem...its worth a while..cheers ivan 😊

Excellent video. Bonus material shows brilliantly, that you not only need to know how to use your scope, but also to understand how to analyze data. Being in the data analytics business, I absolutely love the way of finding insights using the scope and proper analytics.

Gold ! Pure Gold diagnostic and Pure Gold coaching !! Thank you mate !!!

Great diag. Ivan as always. I have used Standard parts for years when OE was not available and had no issues, most of the time even there economy line.

When I first started working on cars I learned a lot from an older gentleman that told me test don't guess don't just throw parts at it cuz half of the time it's a waste

Fantastic fixes. You have more knowledge of fixing cars than most elder mechanics. Good job. 👍

I knew 5 min in this was going to be a good one. Thanks for the scope lesson Ivan. Cheers.

I've been troubleshooting for 45 years you make my head hurt in a good way, absolutely ausum videos, Canada may be centering some content without being registered with CRTC hope to see you in the future, keep up the great work thank you !!!!

Awesome Ivan, great comparison with the scope signals. Thanks for showing all your viewers the difference between the cheap Chinese knock offs verses the OEM equipment replacements.

Great diagnosis Ivan many thanks for sharing this cheers

I had a good laugh at "well, if you dont have a scope, maybe just try using good quality components". And then I saw the bonus bonus footage - fans trying to push air out the front of the car! Waaaaa-hahahahaha!

I bet that was one happy customer. Got his truck all fixed, including over-heating, for the cost of a sensor and a diag fee. Can’t beat it!

I finally got my pico scope a week ago. Now that im learning from you. You can teach this ole dog new tricks. 😊

Great video. Diagnostics is hard enough, then you add DIY with cheap parts and it takes it to a different level.

So nice to have an ace mechanic that lives so close to me if I eve need him. Please don't ever move. 😊

Cheap parts keep you busy, you shouldn't knock them, but you have convinced me which parts to buy, love the bonus clips

You help me stay interested in the sport of auto diagnostics.

Dude, this us amazing content, thank you for sharing your time and talent! 🙏

You are right the cheap parts can cause lot of problem in the vehicle

Thanks for another interesting ride along.....

Im a cave man. If it runs good not over heating and not making scary noises I just drive. I’ve got AAA. When someone notices a light on in the dashboard I say well it’s running good not overheating not making scary noises and not on fire. So let’s go.

Those S10's were the pinnacle of high school coolness. Especially if you had it dropped on wheels.

You have said many times, Oem original parts are the best. That amazon junk did not have a good enough O ring (that would of helped stability), the bracket was shit!. So the sensor was vibrating with the engine vibration. (unwanted modulation) Ill never be a car repairer but Oem parts are a must for critical timing reliability. I wonder which part started the shot gun lol.

Extremely well done Ivan Your biggest fan😊

Great work as usual Ivan. What the hell on the cooling fans blowing foreward.🤦‍♂️

That's a factory lowered truck. I had the GMC version and loved it. Suspension RPO code is ZQ8.

You now have enough experience to be the best troubleshooter of all time (BTOAT).😁😁

Was it really an electrical glitch or a mechanical glitch. When you showed us the sensor was loose and wobbly my mind immediately went to the false misfires being due to the sensor wobbling around. The ECU is constantly timing the rotational speed of the engine by examining those pulses at a microscopic level. The duty cycle function on the scope really proved it out though. Great work Ivan. I really like how you break things down and provide an explanation.

Cool stuff with the use of the scope Ivan. Those S10 extremes usually came a 4 banger. It's rare to see one with the big V6. I've run into this issue before (false misfires) with blazers that have the same engine. And it's almost always the same thing. Someone had replaced the CKP sensor with some dime store junk replacement part.

Great video 👍. This is one reason why i like an exhaust gas analyzer. Although it won't identify a bad CKP, it WILL quickly reveal that misfire counts are bogus.

Ivan My college instructor preached the Saying Kiss saying Keep it simple stupid. I used this saying Keep it stock Stupid. Thanks for posting.

Yes,the cheap crankshaft position sensor was bouncing around due to vibration & causing that 0.5 millisecond time difference in that waveform. The owner unleashed the parts Cannon because he didn't have a scan tool which could read the old class 2 SAE J1850.VPW (GM) protocol PCM which I also have to read fault codes in my 5.7 litre Chevrolet LS1 V8 powered Holden VY SS Commodore. I have had experience with cheap junk sensors in that engine which is why I can't go past the Wells brand of knock sensor which I bought 2:of for $150 AUD per pair in 2019 although I paid only $20 AUD for a new Knock sensor wiring harness which I ordered from a. eBay seller who was located in Hong Kong. I replaced both O2 sensors for about $100 AUD per pair of Bosch sensors in 2012 & I have had no problems with them since then. I was having trouble with the cheap O2 sensors in that car!

Always funny and a bit surprising when Ivan roasts his customers.

I tried swapping a few parts in my 96 F150 Straight Six when it suddenly wouldn't start but had to resort to the diagnostic procedure and discovered the pick up coil in the distributor was bad. Replaced it, reinstalled all the original parts and it's been running perfectly for thousands of miles now. Gotta card one distributor in the glove box in case it happens on a trip. Not easy replacing that pick up coil/hall effect sensor.

I remember my 1995 Jeep Cherokee would have an intermittent loss of spark and a no crank that would occasionally leave me stranded on the side of the road. I didn't have any fancy diagnostic equipment. I had replaced the distributor pickup sensor below the distributor cap (I believe this was a CAM sensor?) as well as the crank sensor on the bell housing both with Duralast components from AutoZone. I'm not sure which sensor was ultimately to blame but I ended up getting two "used" OEM sensors from the junkyard for free and the problem never returned. From then on I learned to avoid aftermarket parts if possible especially for critical sensors like that, which correlates to the issues here with this S10 as well. By the way if memory serves correct I believe the issue was the CAM sensor below the distributor cap, I can't remember how I reached that conclusion as I sold the Jeep 12 years ago, but that's what I remember. If I had a scope I could have tested it. Also being OBD1 my onboard diagnostics tests were just about non-existent as well.

Great work Ivan, I have a S-10 in my driveway, may have to call the Doctor.

Good job Ivan!

Great job Ivan

Interesting diag. Great fix for fan motor installed backwards.

Awww I had a 2001 just like this!! Same bed, extended cab, was victory red with black stripes!!! Miss the F out of it and wish I would have never sold it!

New business for you: "Ivan's Known-Good Waveforms"

Great job Ivan!

Amazing work as always. Used to own one of these, bubbling sound from heater core was fixed with a new radiator cap.

Great video Ivan. If I change a sensor I use OEM. You and Eric say don't use aftermarket and have the case studies to prove it. I do take your sage advice.

Good video! Thanks for comparing the crank sensors. I am in complete agreement with you on cheap parts. I would worry about the amazon distributor with future problems!

Good job Ivan.

Great job….don’t forget seatbelts

Parts Cannon???? More like the Chinese Bazooka...

Great crank sensor tutorial! Thanks much!

I remember working at nissan and having to get a code out of the BCM and input that code into assist(nissans service manual) and generate a code to put into Consult 2 lol. Was nice when 5523 worked for every car

By about 6 minutes in I was thinking crappy aftermarket CKP based on the parts cannon situation and seeing similar phantom misfires in 4.0 Jeeps with crappy CKPs - was not disappointed 😎

Outstanding education. Thanks.

Ivan ... the best thing ive learned from you over the years is to use o.e.m sensors / electrical. I always make every effort now to do so and the shops i diag for hate it . Cause i refuse to diag until they agree to use o.e.m ....

Wow, That "use OEM" rule strikes again! Nice work Ivan!

Awesome job Ivan!!!👍Big brain showin there at the end with that waveform 😂. Genius!!Amazon has become a parts nightmare. I get people wanna save money but usually if cheap does work it doesnt last long.

Oem for sensors only. Don't mess with design criteria at your peril. Knowledge is great but without application is useless.Nice fix on a tricky one.

Stellar! Thanks Ivan.

I had a guy bring me a Honda Passport with an added on aftermarket fan. He was having problems with overheating too. Turned out the fan was wired as a puller instead of pusher. It was pulling heat from the engine across the radiator. He didn't want to foot the expense of repairing the factory fans. Both needed motors and were only available at the time from Honda as a complete assembly. Over 600 bucks for both. It was too late to remove aftermarket fan and fix the OE fans because repeated overheating had blew a head gasket.

I always tell people cheap parts are for Off-road use only. Lol. Nice work PH.

genius man love the content

Crazy.