Idle Control Valve M10

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Jona1971
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Post Mon Jul 14, 2014 6:33 pm

Hello,

My ICV is not working:

1. it receives 13V no matter what the throttle is doing
2. resistance across its contacts is 50 ohms not 10
3. it was shut, i've sprayed it with wd40 to free it and it opens
4. a 12v jumper wire does not get it to close

Any ideas what to check next?
Thank you,
:?
Grrrmachine
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Post Mon Jul 14, 2014 6:41 pm

Point 1 is the most important. If the ECU is not turning off the ICV when the throttle moves, then the throttle position switch isn't working properly. Because of that, there's a chance that the ICV has burnt out through overuse.

What year is this car?
Jona1971
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Post Mon Jul 14, 2014 7:12 pm

Its a 1987 pre-facelift.

This is a (new old stock) replacement ICV as the one on the car when I bought it didn't work.
Jona1971
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Joined: Sat Mar 15, 2014 11:00 pm
Location: Staffordshire Moorlands

Post Tue Jul 15, 2014 5:14 pm

As I have 2, I took the old knackered one apart and its a spring loaded gate where the opening is controlled by a bi-metal strip. As the engine warms up the gate closes and as the engine cools down again it reopens. (Or, I might have that the other way round).

I don't see how it would correct the idle with repect to the TPS, or have anything other than a constant 12v. The electrical connector feeds into a coil. Nothing I can see that moves, just heating effect.

Or, I could be very wrong. Does anyone have any ideas?

:?
Jona1971
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Post Thu Jul 17, 2014 11:45 pm

Right, there is no ICV on my M10 it has an "Auxiliary Air Slide". It helps idle when the engine oil is cold and more viscous. When cold its open and lets more air in and when hot it closes up.

The permanent 12v supply is for heating effect generated from the small coil inside. Its mounted directly to the engine so it heats up quickly.

There is a 7mm adjustment nut on the unit which can help with idle:
1. undo the nut a bit.
2. the thread the nut is on is in an oblong groove and can be moved inwards toward the centre (to lower r.p.m. at idle) or outwards toward the rim (to increase idle).
3. Move nut into position you want listening to the idle and tighten.
4. Idle r.p.m. was 500 now about 650. (not perfect but hopefully no more stalling at the lights).

Hope this helps people with an M10 Chromie. Mr Haynes tells lies... :)