HIGH idle

[KenC]

My M10 has been idling very high lately. When I first start it up and it's cold, it will idle steadily at 2000rpms. When the temp gauge gets out of the blue, the car will fall to its regular 950-1k rpm idle. The idle is very steady at 2k rpms, and still very steady at 1k.
I put an essentially brand new ICV in and it did nothing to alleviate the problem (I've gotta get that back to you, Jordan). I then though that the problem may be my ICU. I acquired another one and it did nothing to help the problem.
I think it must be some sort of electronic control because the idle is steady at all times and it drops down to 1k as soon as it gets out of the blue every time. When the engine is warm the idle is just fine.

Any thoughts?

[BS87]

I dunno, do M10s have Cold start valves like the M20s? Maybe that's it.

[trent]

Ken, I had the same problem. I decided to build an adjustable idle circuit. Unplugged the ICV and put a valve inline that you can open and close in order to adjust the idle. Was a lot cheaper than getting parts -- but real ghetto. :)

[rs4pro3]

same problem here on my 85 318i, never did fix it.

[KenC]

I dunno, do M10s have Cold start valves like the M20s? Maybe that's it.

Doesn't the CSV just help start the engine? It only sprays for like 8 seconds max.

[KenC]

Ken, I had the same problem. I decided to build an adjustable idle circuit. Unplugged the ICV and put a valve inline that you can open and close in order to adjust the idle. Was a lot cheaper than getting parts -- but real ghetto. :)

haha, i'd rather not ghetto-rig something like that.

Do you have any idea what it could possibly be?

The car idles perfectly when it's warm, only high when it's cold.

[trent]

The car idles perfectly when it's warm, only high when it's cold.

Then don't worry about it.

:arrow: :idea: :?:

[BavarianBimmer]

Temp sensor ? :?
I've got a bad contact on the temp.sensor plug ( the one on the inlet manifold)
at least I got one there (blue)

[KenC]

Temp sensor ? :?
I've got a bad contact on the temp.sensor plug ( the one on the inlet manifold)
at least I got one there (blue)

The coolant temp sensor? I changed it about 5k miles ago. It was a used unit, perhaps it's going bad.

Any way to check it with a multimeter?

[BavarianBimmer]

Temp sensor ? :?
I've got a bad contact on the temp.sensor plug ( the one on the inlet manifold)
at least I got one there (blue)

The coolant temp sensor? I changed it about 5k miles ago. It was a used unit, perhaps it's going bad.

Any way to check it with a multimeter?

by measuring the resistance, but can't find the specs immediatly