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Subject:Re: a/c causing rpms to drop when turned on.
From:John Rodgers
Date:Sun, 2 Nov 2003 15:58:28 -0600

If your vehicle is an 86 or newer, there is an idle stabilizer valve
mounted on top of the engine and an Idle speed control box located
forward of the right hand brakelight( pull the light to get to it.)
These two work  together to prevent engine stall by:

1) Kicking up idle engine idle rpm when the AC kicks in.
2) Kicking the idle speed RPM's up when the powere steering is moved to
the physical limits of rotation,
3) Kicing up the idle rpm on a cold start.

Often the one unit or the other will give trouble. If one is replaced,
the other needs to be replaced also. The electronics of the Electronic
Idle Control Box in front of the right taillight, will often burn a
resistor, and then quit. This is a common fault.  These units are
expensive and VW has never supplied a decent replacement.

Regards,

John Rodgers
88 GL Driver
Chelsea, AL
Ki wrote:

>is this normal?  in the summer usually have to turn the idle up so i can
>run the a/c.  is there a fix for this problem?
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