Hello everyone active still, after spending weeks searching through forums and reddit and fb groups it seems like i have a fairly one-off issue, i have a horrible misfire only in 4th gear, under load, i have an 09 2.2L LT that i recently supercharged and tuned, on NGK plugs gapped at 0.032, AC Delco coils and Deatschwerks injectors, i haven’t been able to find what the issue is but it seems after i replaced the ecm for a brand new one it’s gotten slightly less rough, i also ran a compression test and everything looks good there, car is throwing no codes for this either, any help would be appreciated! Video of what its doing as well

 

How old are your plugs? Have you swapped coils and plugs over to different cyls to see if the miss moves? IDK about the 2.2 but the LNF likes AC Delco ok ya and will miss with NGKs

 

I’ve moved everything around and always reads cyl 1, doesn’t matter what’s where, injectors included, plugs have less than 200 miles

 

If you've moved everything around maybe you have a hurt cyl. I would try AC Delco plugs still. I have personally had missing with newer NGK plugs as well as many of my customers I've tuned had issues until putting AC Delcos in.

 

Damn that sucks, i was recommended NGKs from my tuner, and zzp, compression was good when i ran a test as well

 

I've mainly tuned LNFs but most misfires were because of NGK plus. But even on K04 we LNFs guys have misfiring issues with NGKs. What are your trims? If your tune is off it can also miss.

 

Honeslty i’m not sure on my trims, i don’t have tuning knowledge as this is the first car i’ve ever done anything to other than an exhaust and regular maintenance, i’d have to ask my tuner or look at my log

 

It's not important what your trims were but what they are now. Trims are the air fuel ratio error % and if the trims % is high the engine can miss.

 

My throttle body went bad so the cars back apart until tonight, but i can run a new log and lyk what my fuel trims are currently