This is my first post from down-under. I've just purchased a 2001 E39 525i sport with 50k kms. It has a strange hesitation from idle when I attempt to accelerate hard. It seems to relate to the motor as there is no rise in revs, so I don't think it is the transmission. It just keeps idling for a split second and then accelerates as normal. Gradual acceleration is fine, no problems once the thing gets going with kickdown etc-only from idle and only when I try to go hard. Disconcerting when the gap in the traffic is small. Anyone got any ideas? Thanks from kangaroo land.


Aussie 525i

No worries mate. She'll be right! Could be the MAF sensor. Sometimes the flap inside can bind, causing a hesitation. I believe it's a potentiometer. You can try cleaning it first to see if things improve. I've used throttle body cleaner. Not too much though, just a few short spirts.Work the flap back and forth manually a few times, and wipe any excess off.