I wanna hear you call Keith and he says "Yeah, I've seen that before"! 😁

I really wish that I had a local diagnostic technician in my area that is as competent as you are!

Classic case of trying to save money now will cost you twice as much later

Darn it, Ivan. That is not something i expected, i was expecting some sort of ground issue or green crusties. Fantastic effort and scope for the win again. If it was possible i would give more thumbs up. Thank you.

There is a you tube channel called wrenching with kenny. He had a ford engine that he was talking about that kept running really rich. As I recall he determined leaky injectors. They replaced them from a donor engine that they had in the shop. Still ran the same. The engine had aftermarket coils on it. After they replaced them, it fixed the problem. As I recall, he did not quite understand why. I believe the aftermarket coils may have been inducing a voltage in the injectors causing them to open up out of time.

A Dealership would have said, "NEEDS A NEW ENGINE"! Good Job!!!!!!!!!!!!

Throw those coils out the DORMAN!

Awesome job Ivan! Duplicating the problem by bumping up the voltage and zeroing in on the coils was brilliant. You'd think that the guy who replaced all 4 coils would've noticed a slight change in the idle... :-) Eager for the conclusion!

That is nuts!! I don't even have words! I'm waiting on the Amazon Basics Short Block assemblies to become a thing... ;)

I never saw this before. I give you a lot of credit for proving it. I have learned as cars get more electronic loaded the less you can rely on "economy "parts.Thanks

never in a million years would any mechanic near me, would have figured this out... amazing work!!!!!

I remember that RAM that would cut off at high rpm due to a bad coil! So, coils evidently can cause really weird problems.

Great diagnosis. I try and buy OEM parts for my Sequoia. The rear side door actuator failed. Replaced it. Replaced it again. The first was an eBay special. Next one, Amazon. Each one lasted less than a year. In the end, I bought an OEM actuator and two years later, still working. I guess the old saying, You get what you pay for has some truth.

Well done to Ivan and the PicoScope .

Topdon is doing some great things in the automotive industry

Well, this time I had no idea what you were telling us in your diagnosis, Ivan. Nevertheless, you seemed to jump to the right conclusion, which is one of your basic tenets: "Always use OEM parts in critical system controls." Great job Ivan, can't argue with the results. 🙂👍

Ivan's amazing technician

Yup .. Got to check the aftermarket Junk that's been parts cannoned... Wow.. you nailed it again !

Anyone hear that swoosh sound about halfway through? It was just this case flying over my head. Amazing! Great stuff as always Ivan. 👍👍🇺🇸

It's amazing how you still retain your patience after all of the work you've done. If AM parts are found to be defective, a notice should go out to every seller telling them to dump the junk. That's an ideal scernio unknow in the real world. On a side note, AM junk doesn't exist only in the automotive world. I ran into some while fixing a leaky faucet. The parts I bought were advertised for that brand of faucet, but they weren't. I was finally able to find parts from that brand's company. Then repairs became a piece of cake.

Fully expecting a ground issue. Amazing watching how you made the leap to bad coils. Nice job!

The ECM is probably doing voltage compensated dwell to make sure the spark is consistent at various system voltages. So that might be OK. But I guess the coils are junk.

If i've ever learned anything from watch PHAD its to not use crappy aftermarket parts

reminds me of a 2.5 4cyl gm engine back in the early 90s it had brand new ac delco plugs in it. on idle it would run great under load it ran like crap. I tried everything that could cause this. i removed the plugs and they looked fine. after all efforts I replaced the plugs and it was fixed!!

Unbelievably brilliant Ivan! Well done and so intriguing!

if there's one thing I've learned from watching your vids for the last 16 months, it's that Chrysler products and Japanese products require OEM for anything required to use the computers, or it just derps out. and for Chrysler stuff, that also applies to things like the transmission, which requires the OEM fluid or it blows up :P

Love it, was suspecting cheap or weak ignition coils from the 1st video! Always use quality parts people!

You have inspired me. I have bought a bunch of the items you use. I also created an LLC. I've part time repaired cars for nearly 40 years, mostly just to stay current. Your channel is so educational as well inspiring. Thanks from western NC!

I was waiting with baited breath for this insanity!!!

I can't believe whoever fitted the coils, didn't question why it was running like junk after they'd worked on it. Nice fix Ivan.

Good job you have a Y.T. channel to justify your time on this one Ivan! Wonderful use of the 'scope - most auto guys over here wouldn't know how to use one.

Never would have expected that. I kept telling myself is a bad ground. Nope! Mr. Ivan saves the day. Great find, master.

Those must be the 6 volt version coils, and they were going into over voltage shut down. I knew it the whole time! 😄

Seems like I remember this guy that runs a small shop in Upstate New York that said one time that there are mechanics that can look at a waveform and tell you what color underwear you have on even though he didn't have that ability. Ivan, I think you were one of those guys he was referring to. You, Keith DeFazio, Brandon Steckler, and many others have that ability. I wonder what it is going to be like when I need to change a COP on the 'ol Marquis? Oh! wait, it doesn't have COPS. I don't think your Mystique does either. GREAT VIDEO!

I've found NGK and Denso to be OEM equivalents when it comes to coils for many Japanese vehicles such as Subaru, Toyota, Suzuki, etc. Usually around half the price of the actual car manufacturer branded OEM coils and actually, many times the car brand OEM coils are actually made by NGK and/or Denso anyhow lol.

Ivan. I LOVED your diag. I was with you all of the way. I was a "High resistance" guy from the get-go. Wrong

It would be nice if you could go to the white board and explain what the hell you just did and thought process behind it

Thanks Ivan. All that Subaru needs to be perfect (aside from the coils) is a STICK! Look forward to the next installment.

That sure was an odd one! Good straight forward diagnosis with no parts cannon fired. My hunch was the pcm did not like the 14.5 volts and was going into some type of over voltage shut down.

Wow very nice diagnostic,amachinazon coils transistor low quality 50%Cooper only..good job.

Amazing! I would never think a coil would do that. You really know your stuff Ivan!!

thank you for your time, you are educating mechanics around the world I have been fixing cars for 64 years never too old to learn

This reminds me of that Dodge truck you worked on about 4 or 5 years ago down on Staten Island. Where you would rev it up until hitting the rev limiter and the engine would stall out because of one aftermarket coil.

Well, I was completely off base. However, I once again learned from a master. Thank you for sharing (as always), Ivan.

Watching that change in voltage ramp up and what it did to the engine running, at first I was convinced that the charging system should never go over a certain amount to maintain a low stress level on the electronics. Having the "programmable" Top Don charger/maintainer proved that. Then came the swap with the used OEM coils which probably have that built in voltage level maintainer circuit built in. You proved where the problem is located in the junk coils. But the question in my mind remains. The charging system output can cause multiple problems in other electronic parts such as the fuel injectors, the PCM/ECM, the fuel pump control module, the pump itself and other "actuators." Who knows what it does to the wiring harness/connectors over time? My 06 Nissan Frontier has a normal charging voltage of 12.9 shortly after the engine is started up. Now I know why. The ECM controls and maintains that voltage but can increase the generator current output as needed depending on the load. That was definitely an enlightening moment Ivan, another way to diagnose an engine running problem, and the "WHY" the charging system voltage should be kept at a certain level. Sorry for the long comment, but it definitely was an eye opening, learning moment.

That was epic, I haven't seen that since the old GM injector days

Is that Takata airbag, watch it, it could blow your mind. 🤣🍻

Hypothesis proved! Awesome diag.. scope to the win!

Throwing test coils away!! Keith would be slapping you and he would smile lol. I did wonder if the coil earths were crappy. A keith reminder :-D

Amazing! I'd never have thought of that, it's a real weird one!

Nice! It seems the the dielectric of the secondary was falling internally with higher voltages and the electronic circuit was disturbed.

If you let the gauges do their key on sweep after battery disconnect of code reset it will restart normally without excessive cranking

Hats of to you sir , every other shop would have put 5 alternators on it by now and still scratching there head 😂😂

Somehow when I’m down and out you always save my day.

Your only 2655 miles away, so next time I have a drivability issue I'm heading your way. Great to see a tech that enjoys a challenge.

The sad state of the quality of aftermarket and sadly some so called OEM parts has brought many challenges to technicians when they are already challenged by the complexity of modern electronics in the industry.....My nephew has just got his first scope ...thank you for helping others understand the importance of through diagnosis before firing the parts cannon...Karl from eastern Canada

Amazing to think the previous owner gave up on the car and sold it to the shop for I guess not very much and all it needed was 4 coils (and a professional diagnosis). It feels like they got cheated out of the car because the shop could not find the problem and the owner did not want to keep paying for them to fire the parts cannon.

Awesome diagnosis Ivan! I can’t imagine figuring this one out!

Great diagnosis and repair👍👍👍

Great find! You had my brain working overtime. Just amazing the havok that can be had with knock off, cheap, Fleabay, and Scamazon parts. Unbelievable.

Definitely a strange trigger for the problem. NOT strange that a no name electronic part is the problem.

Your brain is like a heat seeking missile. Love it. Great work as usual.

And that kids is why you buy OEM. Any savings you might have had was spent chasing the problem. Junk parts made the owner sell the car. That cheap parts price don't look so good now, does it?

You could have asked the owner where they got the coils & that to me would have made me suspicious of them which in turn would have made me get OEM coils & fire the parts cannon with reasonable confidence Cheers Ivan.(I do not have a scope so that is why I would have made my diagnosis as people see a cheep part & want to save money not realising quality counts & a bit more money spent would have saved your diagnosis charge.)

What a case study! Way to troubleshoot, Ivan!!

You view a challenge as fun and not somethig to whine about. Such a pleasure to watch your amazing skill and talent!!

I didn’t see that coming. I thought it was a short in the engine harness that included the alternator wires. I guess I would have been down a rabbit hole on this one. 🤣🤣

I just can’t believe someone had it towed from Philadelphia to state college just to get him to fix it. That’s crazy. I wonder what that tow bill cost him? I think a few videos ago someone had a vehicle towed from Ohio to State College for him to fix. Jeepers

This Subaru reminded me of a full-size Ford van I once worked on. It ran really bad when first started, but smoothed out in a minute or two. Disconnected the alternator, no problem. I measured the ripple, off the chart. The customer did not believe me, told me that it was a new unit (Manny-Mo reman) and that I was trying to rip him off. I told him ok, but leave it disconnected on his way back to Manny-Mo because it was throwing sparks out of the case. Never heard from him again.

ABSULUTLY BRILLIANT i would have put money on more voltage bigger and better spark thanks for the insight and videos

I had bad powers and grounds to ECU or bad drivers pretty soon in ep. 1. That turned out to be wrong, but then in ep. 2 I finally saw the schematic where the coils get both power and ground and thus turned out to have the driver circuit integrated in the coils. It would have helped if you explained that the drivers were integrated in the coils from the start for us home players to do our arm chair diagnosis. Not sure if you said that there were brand new aftermarket coils in ep. 1, but that would have also been a dead giveaway to concentrate on those, especially with the built in drivers.

Top diagnosis and fix. Like you I've never seen that before!

I'm still scratching my head over this one. They didn't do you any favors by informing you about unplugging the alternator. If you didn't know about the alternator you would have correctly diagnosed the problem much sooner. Good job! Love the content!

Pretty neat. Thanks Ivan!

Nice job Ivan! I would have still been pulling my hair out 🤯!

Masterful diagnosis and repair from a master mechanic!👏Bravo!

Hi Ivan ! I know that ECM takes a count on system voltage for the fuel injectors. Possibly, it does the same for the ignition coils if a triger time changes with the voltage. Nice job Good luck

Thanks for the video Ivan.

One of the best case studies so far! Kudos!!!

Those coils remind me of an old 62 Jag I had 45 years ago... The thing ran like trash when I got it, which was the reason I got it pretty cheap.... I noticed it had a Ford coil on it, and of course the Jag is English with Lucas electrics with positive ground, whereas US domestic cars had negative ground. There was a discarded Lucas coil in the trunk so I tossed it on and viola! The thing ran like a top. (Ultimately the reason they changed the coil I suspect was due to a blob of something in the gas tank that would come up against the pickup every now and then, and the thing would quit. I'd go into the back, pull the hose off the electric pump and blow into the tank until I got bubbles. Put the line back on and trick the electric pump to fill the SUs and I was off to the races again! ) So I wonder if those coils were designed for a positive ground system or if the +/- were mismarked. It would have been interesting to reverse the wiring just to see if it made a difference.

Anybody run into fake plugs yet? If it’s a “great deal”…….. mmmmmm but was it.? Thanks for GREAT videos 😊

Well i never saw that coming, unreal. Ignition coils that dont like voltage is crazy LOL.

Chineseium? I like that. lol. Now I've seen coils flat out die. I've seen them explode. I've seen them short out and I've seen them catch fire. But I've never seen this before. Great case study for sure.

Great case story and investigation on the problem. Good job two thumbs up.

Ivan don’t do a scotty Kilmer. Had you told us there were 2 aftermarket coils it would have been a. No brainer

Amazing it was the coils. I wonder what the difference was between the crappy aftermarket junk and the originals. I have and inductance tester. I wonder if the inductance is the same between them. I bet the increase in voltage from having the alternator hooked up was just enough to cause a breakdown in the insulation of those Chinese junk coils to cause them to arc over. I would put them on a bench power supply and power them up in the dark at 12 volts then at 14.8 volts and see if there is any arcing externally or if you hear anything internally crackling. It would make a good video. None the less you are still and outstanding tech.

Brilliant thought process in this diagnostic, Ivan!! I couldn't believe it was true! This is another cautionary tale about aftermarket parts - this weird problem wouldn't exist with good coils. Now wondering what is causing the parasitic draw - probably nothing as spectacular as the coil problem but, who knows 🙂

Wow great job! Scope for the win!!😂

Awesome Diag Sir! 🍻🍻

The parts bin has a cannon in it! But the cannon's aim was true!

Ivan, you rock in my book always what a case study with this vehicle alternator connected run bad and alt disconnected will run ok this will confuse even the master technician and will be throwing parts on it left and right ur approach and thought process always amaze me and with out a scope this will be really hard to fix for sure and by the way i start working for KIA dealer no body knows how to test not guise they just through part at the car and hope it fix it AWESOME fix and thanks for sharing. cheeeers

Oh Chinesium... Gotta love this one. WOW! This is why I buy OEM or reputable brands (where OEM aren't available). It's worth the price!

The yinyang specials strike again

Ivan I wonder if the coils are wound wrong internally. Would have been nice if you had Put a paddle probe on the coil to see which way it was firing.

Great reveal !

WOW! HOW THE HELL IS THIS THE CAUSE OF THE ROUGH RUNNING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! GOOD FOR YOU TO TRACK THIS DOWN!

This Subaru weirdly reminded me that poor Mazda fried by that reckless welding job and needed a whole new wiring harness (not worth it) to work again

Ivan says That's pretty amazing, I like this car ! The challenge is on, see who the boss is Zoobarooo! Ivan for the win.

Very interesting, no green crusties this time but aftermarket junk parts. Have had my share of subpar aftermarket parts too in the 90's and 2000's, cheapest junk isn't worth even that low price, they are just trash.

Fantastic video, my favorite, hope it’s ready for morning coffee