Re: 1990 Coupe Q

[schulz@iatcmail.ed.ray.com (Peter Schulz)]

Brian Gimmet said:

, and I own a 1990 coupe quattro and Ive had
> little problems with it. But there are a few things that I have
> questions about.
> 1-   When I slow down quickly the idle drops to where the car almost
> dies.

The general concensus amongst 20V owners has always been that this
was an idle stabilizer valve (ISV) problem. The usual recommendation 
is to remove the ISV and thoroughly clean it with carburetor or brake
cleaner.

After doing this, and even replacing the ISV (big $$$), I still had an
intermittent problem. Slowing down would still occasionally cause the
rpms to drop below 800rpm, and occasionally stalling.

I think that I finally found the solution. I noticed that the idle 
switch on the throttle body did not always audibly "click" when 
I manually played with the throttle (working under the hood).

I removed the switch and tested it mechanically and performed a 
continuity test.  The switch passed.  When I reinstalled the switch,
I realized that I could adjust it's position against the throttle
tab. After reinstalling it, I again worked the throttle to ensure that
the switch was audibly clicking. Now the CQ maintains the it's idle as never
before.

> 2- If I hit the brakes hard the brake light comes on briefly.
> 
You need a new hydaulic pressure accumulator (aka "bomb"). Check the
qlist archives, or email me privately for instructions for CQ bomb r&r.

HTH
-Peter Schulz
1990 Coupe Quattro
schulz@res.ray.com