engine is idling at 3k rpm

[Graham325]

Any idea what it could be? I figure my afm or icv, but I thought somone might know from it being stuck right at the 3k mark? is there any way to test out which it could be? Thanks

86 eta btw

[AndrewBird]

I would check your throttle cable first. It could be sticking. I don't think an ICV will let the engine idle that high. Could be wrong though.

[winstontj]

Is this new or has this been the case for a while? What changed? tune up?

always or sometimes?

[Graham325]

I was sitting at a stoplight and it jumped to 3k, I pulled over messed with the throttle cable and its ok.
the only work on the car recently is new fuel pump/lines.

I havent fussed with it much after I got home. I have tomorrow off so I will be able to get in and see if I can find somthing.

[H&Re30]

check the green box...not sure where it is...but my mecahnic told my buddy (his car idles and dips from 2500 to 600...really weird) but yah, he said it was the green box, which runs about 250 used...

[Graham325]

wtf is a green box?

[mulishaflesh969]

ICV would bring it down. it should. if it didnt, its the ICM in the glovebox... i got one for sale. its a green box as well (best as they come now adays).... let me know.

i also have a extra ICV. and TPS. all of these can help this problem.

not the throttle cable. UNLESS of course you have a little throttle body gremlin who likes to readjust things in the dark.

[mulishaflesh969]

and i wont charge you 250 or whatever. they are expensive. but seeing you need one, and im low on the money, and im not using the extra one... ill sell it to you for cheap. my loss senor.

[mulishaflesh969]

the 'green box' is aka the ICM. Idle Control module. some people say IC motor.

[DaveSmed]

Does your idle switch work? I believe Motronic had a rev limit of 2500 with the idle switch closed, which is that surging idle problem that shows up on many older e30s. The boxes burn out then they sit there and slowly bounce of the low rev limit, like mentioned in H&Re30's post.

Try adjusting the switch first.

[winstontj]

If you UNPLUG the ICV the motor should rev up to ~3,000rpm so if you have a faulty ICV or if you have no power coming into the ICV then it gets stuck open (or more open) and your motor will rev. Do you have a 2 or 3 pin ICV?

You should have an idle control module (ICM) which will be in the glovebox next to the ECU. Open the glove box and look up. Grab one at the wrecking yard for $5 (unless it says BMW on it say you got it out of a Corolla or something). There are tons of eta's around Boston so you should be able to find one wherever you are.

[Low Level E30]

My car likes to idle at 2k. Is this the ICM also, you think? It is rock-solid at 2k.

[mulishaflesh969]

do this....

1) turn off car.
2) Open hood
3) Unplug ICV
4) Grab Brake Parts Cleaner
5) Spray it all out. literally
6) blow it out with air / or let dry
7) replug
8) Dont connect the wiring at the bottom
9) Start car

If it runs fine, just needed cleaning.
If it still idles high - ICM is out.
if you replace the ICM and it still fucks up, ICV is out.

[Court M3]

Old thread bump

what about cars that didn't come with an ICV? My 83 323i didn't, maybe I';; find an E and swap out the ICM

[Coco Savage]

well glad i found this thread im having a similar problem.... except mine idles around 1500 then when i stop and depress clutch pedal it revs up to 3k.....

would checking it by cleaning be a good start?! Or do i possibly have a far worse problem?
Thanks for the help!





sorry to bump an old thread, but i didn't think i should start a new one for a similar problem