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DISCUSSION => Engine management => Topic started by: colin86325 on April 15, 2013, 02:33:49 PM

Title: Does your ICV "buzz"?
Post by: colin86325 on April 15, 2013, 02:33:49 PM

Can anybody go out to their car and test whether the idle control valve buzzes or hums when the engine is off but the key is in the Run position? If you can't hear it, test with your hand and see if you feel a vibration.

On my E30 M3 you can hear the ICV buzzing clearly.  But my 318iS does not buzz.  Likewise, on my girlfriend's 318i M42 there is no buzz either.

I'm wondering what is supposed to be normal.

Title: Re: Does your ICV "buzz"?
Post by: DesktopDave on April 15, 2013, 04:12:24 PM

My M42 units buzzed when I tested it with 9VDC...but the one on the motor never did.  I don't recall the M20 units doing that either.

Title: Re: Does your ICV "buzz"?
Post by: colin86325 on April 17, 2013, 08:19:16 AM

Thanks Dave, so it did not buzz on the car.  This seems to confirm what I have experienced.  Maybe Motronic 1.7 uses a diffferent control mechanism (like a stepper motor) vs the Motrolic 1.0/1.3?

Anybody else?

Title: Re: Does your ICV "buzz"?
Post by: deansweet on April 17, 2013, 10:34:01 AM

I did the turn the key to on and check for buzzing and neither (91' M42 318i and 318is) of ours do this buzzing you speak of?
We need to find another E30 M3 owner to check?

Title: Re: Does your ICV "buzz"?
Post by: colin86325 on April 17, 2013, 10:59:29 AM

Thanks Deansweet!  So we have 5 M42 samples where there is no ICV valve buzz.  I think this confirms for me the proper behavior for the M42 ICV.

For the E30 M3 I'm about 95% sure that it is supposed to buzz.