'02 325Ci is a Cold Weather Whistler

[ladydi]

Still have this issue and need some advice please. 2002 325Ci, 47,500 miles, has a whistling noise in the engine when it's very cold outside; temperature has to be below 40 for it to occur (yes, that's very cold to me).

Also, when this happens, the engine occasionally revs itself (up to about 1200 RPM) when sitting still (i.e., stop light). Once the car warms up, the noise and the revving cease. Has anyone experienced this? Should I be seeing a mechanic????....

I'm relatively new at owning a BMW (less than a year) and I need your experience.

[Scany]

Sounds like you might have something going on with the vacuum system. This is a little pain to figure out. I'd start by looking for a cracked rubber hose, and to try to pinpoint exactly where the sound is coming from. It might be cracked hoses or the idle control valve that is making the whistle.

I have sort of the same issue and that's what I have figured out so far in my case. Just my 2 cents