really rough idle

[doublea]

When I start my car, it idles at about 750rpms like it should, but intermittently when I idle at stop lights and stuff, the rpms will drop to about 300, and all the lights on the dash will light up, then the car quietly dies. There is also a whine coming from the engine bay in first and second gear, between probably 1500-2200rpms. I think the crappy idle might be the alternator/drive belt?

Any thoughts?

Thanks!

[jlevie]

The bad idle is probably intake leaks and a sticky ICV. Other causes are possible, but start there.

[bmwm42]

Yup you for sure have a nasty leak some where and our a very badly stuck icv

[crazyman]

Yeah it does sound like the icv is gone. Weird though cus when mine died on the 84 m10 the idle spiked to like 2k and stayed there.