[f32christian]

hey everyone let me give you guys a background i drive a 15’ 428xi, i’ve done some engine modifications like catless downpipe, fmic, chargepipe. i’m stage 2 tuned w bm3

today i started my car in the morning, to a drivetrain malfunction. i instantly turned the car off read the codes i have a bunch of codes for cyl 4 misfire and injection deactivation, combustion period too short, damaging exhaust gas after starting up, those are all my carly codes. after i cleared the codes my car is now running perfectly fine to my knowledge.

this is just very odd to me, ive recently changed spark plugs (when i tuned the car) coil packs i’ve changed when i first purchased the vehicle (within the past 6 months)
i don’t really know what the next step is
anyone have any similar experiences?

[f32christian]

small little update i replaced cyl 4 spark plug with an old one and swapped cyl 4 and 2 coil packs so if i get the drive train malfunction again at least ill cancel out spark plugs and coil packs.

[WeAreVenom]

Similar thing happened with mine at 92k. Changed coil packs and spark plugs and it went away for a month. Came back and the issue ended up being the high pressure fuel rail. It’s been perfect since

[f32christian]

WeAreVenom
thanks for the feedback, i’ll keep that in mind. how did you end up diagnosing that?

[WeAreVenom]

Dealership when nothing else fixed it. I just didn’t have combustion period too short, in place of that I had mixture too lean pop up after changing coils and spark plugs. Used BMW fuel additive, replaced the fuel pressure sensor, was going to clean the MAF sensor but it was completely clean, no leaks so I was stumped. Dealer wasn’t certain if the issue would persist but it’s been another 2k miles and no more issues

[f32christian]

WeAreVenom
hm, yeah it’s just very odd. i cleared my codes and literally runs like nothing is wrong. i guess i’ll have to find out if or whenever it returns

[WeAreVenom]

yeah same with mine, but a couple days later it would just come right back. Sometimes would go into limp mode some times it wouldn’t. Just a system precaution and not an actual failure I suppose but if ignored for too long would probably cause serious and more expensive issues