440 B18U (1.8i) idle problem

[Dan F]

Hi.

I have a friend who has a 1995 1.8 Si 440 with 51,000 miles on the clock. The car is great and pulls very well indeed. However it does have one problem....
The idle tends to settle at about 1200 rpm. This doesn't seem dependant on temperature either. The idle is stable however.
The local dealer has replaced a couple of tubes that can get blocked and this lowered it a bit, but that was only from 1400 to 1200.
It only seems to idle correctly when first started but then creeps up slowly.
Does anyone have any idea what is or may be causing this?

Any help appreciated.
Cheers,
Dan.

[Dan F]

I have read elsewhere that it could be the coolant temperature sensor that is faulty, telling the ECU that the engine is always cold, and over fuelling it and keeping the idle too high.

Does this sound pheasible?

Any ideas?

Cheers,
Dan.

[Martin Cox]

I had a similar sounding problem with my B18U engined 440. It turned out to be a faulty stepper motor which I believe sets the idle speed. Fortunately it was replaced under warranty.

[Dan F]

Thanks for that.
I will question the dealer with that info.
Any ideas how much a stepper motor is?

Dan.

[Martin Cox]

Unfortunately I can't advise as to how much the part costs because I neve saw the invoice. The service department passed it straight on to the warranty people. I believe the Haynes manual describe it as an 'Idle Speed Control Motor'. It's possible it may respond to cleaning but I didn't mess with mine since it was still under warranty. Hope this is of some help

[Dan F]

Cheers.
Might be worth a 'fiddle' then....
If that fails I will have to inform the poor soul of an impending dealer trip.

Dan.

[Mav_UK]

My dad just had to replace the Idle Control Motor on his Omega, was 120GBP fitted I think, I think that he had to have it fitted (at a dealer) as when the plug it in they have to talk to the computer, he is a mechanic and would not have paid for fitting if not absolutely required. Don't know if volvos will be the same.......

Good Luck

Stu

[Dan F]

Thanks for the info folks.
Sounds like that may be it.

Dan.