1.6 m40 baby i know . what control voltage is sent to the I

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arrisbmw
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Post Fri Sep 28, 2018 6:10 pm

I,C,V , anyone know what control voltage please , is sent to the idle control valve , 5 volts or 12 volts ?

1989 year.
I,m trying to trace an issue with cold starts, my icv has power to it but is not in the open position,
I,m thinking maybe someone has fitted the wrong one, ( 2 pin type )

thanks any advice , appreciated . or circuit diagram would be good.
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Brianmoooore
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Post Sun Sep 30, 2018 5:21 pm

It will be a voltage dependant on what correction to the idle speed is required. Never had occasion to measure it, but AFAIK, it will be a maximum of 12 volts.
Note that this only applies to the M40 (and most other engines in the BMW range) - the M20 uses a different type of ICV, consisting of two motors fighting each other, rather than one motor fighting a spring.
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arrisbmw
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Post Mon Oct 01, 2018 9:19 am

thanks Brian , I was hoping you may answer , my Q .

the issue I,m having is the idle does not change at all even with a stone cold engine just stays at 600 ish ,
the valve is moving from its resting semi open position to closed with engine running.
if i remove the power to it. revs go up to about 1200. so it must be getting something

I,ve fitted a new blue temp sensor.

thanks again