[paul_80eighty]

Hey guys, I’ve owned my F13 M6 for around 8 months now and love it. However I’ve run into an issue that started about a month ago.

When in 2nd gear or higher, I noticed a stutter/hesitation when doing a pull. This problem started gradually. The first time it happened I wasn’t even sure if I fully noticed it. The next time, it threw drivetrain malfunction at me. This would happen at 75% throttle or more.

For context, I’ve got aftermarket charge air coolers, Charles’s DPs, fatback exhaust and an ECU tune.

So, I changed out my plugs to NGK 97506 1-step colder gapped to 0.024. This did not fix the issue, although it was time for a plug change anyway. Then, I changed out ignition coils. This did not fix the issue either. Finally, I changed out the injectors in bank 2 (since the misfire is cyl 7). I really thought this would fix it, however it did not. I did notice a slight improvement - I had to drive a bit harder for it to throw the code again. But regardless, the issue persists. The only code being thrown is cyl 7 misfire.

I’ve tried reverting to stock tune without success. But in doing this, I noticed it took driving the car a bit harder as well to get it to throw the code - which makes me think it’s still a fuel system issue.

Idle is smooth, and driving the car normally I don’t notice anything wrong whatsoever. It could be so many things, but wanted to see if anyone has had this issue before where there’s a persistent in one cylinder only under load heavier load (1st gear pulls still rip to redline with no noticeable issues). I haven’t noticed any unusual smoke from the exhaust or any unusual smells either.

Thank you for any input!