Was doing a 3rd gear pull and car backfired at about 6.2k RPM and went into limp. Threw misfire codes and exhaust sounded like ****. I limped the car home and pulled the plugs and found this...





Yup you are seeing that right, it has not electrode...

This is what the car sounds like, this is before I took the plugs out obviously...



Let me know what you guys think, what steps should I take..thanks!

 

Ask this guy. ^^^^^^





















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Compression test!!!!

Whatever it is.... it's going to be major I'm pretty sure.
Maybe you dropped a valve. I wouldn't run it any more.

 

Yeeeaaaahhhh... Sounds like the, "Subaru Sound of Death" to me. You may have busted a ring land in that cyl which could have sent metal into the spark plug which would destroy it. Is it buring oil really bad?

Also, could have jacked a valve which could have broken a piece which would have destroyed the spark plug. Looks like a lot of oil on the plug though. Take valve cover off and look for broken rockers or lifters on that cylinder. Taking it off is relatively easy, just a series of 10mm bolts.

 

Why does the car sound like Subaru sound of death? Because he's only firing on three cylinders. Back onto topic, he logged when this happened. No kr, no issues until he let off because the misfire. And on the decel he got 2.kr . Idcs, the temps, all look good. The only things that could cause this is a. Piston somehow hit the grounding strap (less likely) b. foreign object made it into the cylinder some how (possible but less likely) c. Injector is leaking causing unmetered air to leave and come into cylinder causing the electrode to be broke off (less likely) d. Spark plug grounding strap was **** and just broke off . It does happen not to often but it does. In the case of how, it's usually caused from bending the grounding strap to much. And the plugs were gapped I believe when he go back home .

Afr was mint, timing was direct and 25* at the time, fuel trims were mint, (even though the egts on rear o2 is based on calculations) it didn't get higher then 1500*, idcs were 30% and all others normal. So the explanation of how it happened is doubtfully a piston fault, or any of the less likely above unless it was a mfg error.

 

I also asked, " is it burning oil"? Op states no.. And there is no oil on plug, it's all raw fuel.

 

^BTW first thing I did was message James, as he is my tuner and my friend. **** happens, have been rading up and talking to James and I will start diagnosing the problem here in a little bit! First things first, some new plugs and compression test!

 

And the only other thing is heat range. If the heat was to much for the plug you could preignite from a hot spot in cylinder. Also known as deiseling. But those plugs were just installed and gap was looked at but not changed. Stock plugs

 

Did it backfire while you were still on the gas or when you let off? Was it a single backfire or was it a rat-a-tat-tat backfire?

The electrode obviously melted off. The hard part is figuring out why.

 

He had misfiring issues when he got bac to Chicago so I remote tune him with his tuner and I had him lower gap down. One of the things I suspected was a injector seal.

This issue (grounding strap breaking off) is common in motocraft/autolites plugs and is very common is fords.

 

I'm not a tuner but I always did wonder why with any little thing everyone automatically just points fingers at the tune.
Like one of ZZP's threads "Can I get a retune bro?". Everyone jumps at the tune when 90% of the time it has nothing to do with it.

People should just start at the first step (Compression test here and change plugs as the OP plans to) and just see where it leads you. If it leads you to the tune, fine.

This might be coming off as an asshat. I'm really not trying to come across that way. I'm just trying to be... informative I guess. Anyway, good luck to you OP! I hope it's as simple as a faulty spark plug and no real damage.

 

Oh no one is pointing fingers at tune at all. Actually this happened while logging and tune was spot on. Freak accident I suppose. Took the valve cover off and everything looked fine. Next went to compression test and found out that I have 0 in cylinder 1

 

OP edited his original post. He also updated his signature to remove the "e47 ChevyCobaltSS3 tuned." Wonder who asked him to do that... LOL

At first OP said he had just loaded a tune and was datalogging it when this happened.

The fact that it blew up immediately after uploading a tune tells me the tune was at least involved.

 

Ahhhhhhh... gotcha. Understood.

 

**** this just happened to me on the way home today but mines in cylinder 2.... fml, luckily not working tomorrow so i have plenty of time to work on it and figure it out.....