Weird acceleration problem

[rjs172]

Hello everyone, so my manual 1999 318i started acting weirdly when accelerating in 3rd or higher gear. Basically when I try to accelerate while cruising it doesn't want to go past 2000-2500 rpm's. However, if I press the clutch pedal while trying to accelerate, the engine revs up freely, making me think there's something with the electronics and not with the engine. This strangely doesn't happen while i'm in 1st or 2nd gear. Does anyone have any ideas, as to what could cause such problems? Thanks

[B1mmerB0y]

Not sure it is the same problem, but I had a similar problem with a manual 01 corolla where in any gear, it bogged out and acted strange once it hit 3000 rpm. Replaced much of the fuel system up at the engine side and ended up temporarily fixing it with larger, Pontiac Vibe injectors out of the junkyard. However when replaced with stock junkyard injectors (not the set that was originally in it when problem was first happening) the problem continued. now it runs rich but doesn't act strangely at that 3000 rpm mark. May be an electronics problem and the larger injectors spit out enough fuel to just get over whatever is choking it up at that RPM. Like I said, not sure exactly what your problem is or even what mine was but now it runs and drives with the only problem being it running rich and throwing a engine code.

[B1mmerB0y]

This thread someone seemed to be having a similar problem and says that their throttle body was at fault.
https://www.bimmerforums.com/forum/s...ration-problem

[RobertDenali]

It could be throttle body, computer, ignition system or fuel system.

First check codes and see if you are getting freeze frames.

Next clean throttle body and idle control valve (only because you are already there), then check fuel pressure etc.