High Rev/ AC problem

[Coco Savage]

Hello all Im new to the e30 world and i recently seem to have this high revving problem. The engine will rev up to 3k on its own when im at a stop, but the thing i discovered is it only happens when the ac is on.

It literally will rev up to 3k when i hit the ac button, and then go back to normal idle when i turn off the ac. To further confuse it doesnt always happen when the a/c on.

Does anyone have any help on the matter?

[jlevie]

Sounds like an ICV issue. Remove & clean the ICV. The internal vane should move when you rapidly twist the ICV.

[Coco Savage]

really so even if its only during a/c?

[Wishno87]

my idle gets a little whacky too when i turn on the ac sometimes. it bounces between 1000 and 2000 and finnaly settles around 700. its at around 600 without AC

[Coco Savage]

anyone else?

[Coco Savage]

help?

[Coco Savage]

Ok well remove icv and cleaned it. Now the problem is worse as it does the high rev'n with the a/c on or off. :(

wtf!!!

[chrisesteschiro]

get a new icv.........I have one for sale for 40 bucks shipped, L stile, as opposed to the T............

[EtaSport]

I can tell you how to make it go away, but i cant tell you what causes it or how to ultimately fix it.

Your A/C switch is tied to your DME with a simple on/off signal wire. Pop off the panel in the left side of your glovebox and look for the purple and red wires connected together. unplug it, and your idle will be okay. This is present so the idle will raise up 100 rpm when the ac is on to keep things okay with the extra load.