I have a 1999 323i.
It makes a noise when I step on the Gas at low speeds (10 - 20 Miles/Hr).
Like metal vibrating or Grinding or hitting against something real fast repeatedly.
It could also be there in high speeds, but I can't say because of the other noises.
It seems like its coming from the Right Front side of the car. May be near the wheel. Can't say really, coz the car is moving and I could be hearing it at a different place.
Its not from the A/C as it comes when the AC is off too.
I tried to get it on Audio Tape, but no luck ( Stuck a Recorder with Duct Tape and Drove around). There was audiable sound, but the tape did not get it.
It sounds like.
Its driving me nuts.
Any help appreciated.