Random Engine Stutter when warm/heat soaked, idle and during acceleration. VIDEO!

[jameskarger]

Car is a 96 328is, been experiencing the problem for a few weeks now and it seems to be getting worse. I do not notice the problem when the car is cold, but after 30min of driving or after the car has been driven and restarted (heat soaked) the problem is pretty much always there. The engine will stutter, like a real quick bad miss, almost like the engine dies out for a split second. Sometimes this will also happen during acceleration, the car will accelerate, but just a couple of quick random misses throughout the power band. I have attached a video, this is at idle and you can see 2 times where the idle falls, thats when the car feels like it is missing/stuttering.

Car has had the IAC cleaned very recently, has a new oil separator, plugs are a year or two old, no vacuum leaks that I can tell (just had the intake off not long ago for a starter replacement). Ran fuel injector cleaner through with no affect.

Seems to be a problem that is only present after a good bit of driving or after the car has been driven and is restarted (ie heatsoaked).


http://s48.photobucket.com/albums/f2...t=IMG_0492.mp4

[jackxc925]

I have been having the same problem, I think it may have something to do with ignition though. Maybe heat is increasing resistance in the coil packs, and causing a bad spark. Here's my thread: http://forums.bimmerforums.com/forum....php?t=1551639

[jameskarger]

Do you have a CEL, I do not.

[jackxc925]

I do not

[jameskarger]

ttt

[jameskarger]

Nobody?

[fun2drive]

I don't think you have an issue with coils because they seldom fail when at idle. Loss of rpms at idle sounds more like a vacuum leak. Doesn't sound like a fuel pressure issue either because the engine runs well except for the occasional miss or rpm drop. Typically a vacuum leak is there all the time but this seems to come and go.

Heat soak sounds like a coil that is bad but again I don't recall ever seeing one do this when there was no load on the engine....

[jameskarger]

Thanks fun2drive, the car overall feels slugish, it may very well be a vacuum leak, so hard to see all of them on these cars, I did have the intake off when I was doing the starter, could have a bad connection.

Any other ideas?

[Major1997]

Thanks fun2drive, the car overall feels slugish, it may very well be a vacuum leak, so hard to see all of them on these cars, I did have the intake off when I was doing the starter, could have a bad connection.

Any other ideas?

Did u find a solution?