Idle problem SOLVED

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <970827094049_1159181352@emout18.mail.aol.com> Moinx3@aol.com writes:

> I'm happy to say that it was just a well disguised vacuum leak. See, I also
> have an exhaust leak in the premuffler that creates a hissing sound so I just
> thought all the hissing was from the exhaust.  The vacuum leak came from the
> hose that runs from the intake manifold to a union that is coming from the
> valve cover-I think it's purpose is to scavenge some crankcase gas.  This
> particular hose suffers from a lot of heat cycling and had (over the last 7-8
> years) degraded the rubber enough to cause failure.  After putting a rubber
> cap (a small rubber foot to a chair bought at ACE hardware) over the fitting
> on the intake manifold as a temporary fix, my car now idles at 900 rpm with
> no unusual fluctuation.

This is actually how the car should be set up - this hose _should_ be 
disconnected and plugged during the setup procedure.  _VERY_ few garages 
actually follow the Audi instructions to do this.

> Most of the replies that I received had been to check the ISV.  After solving
> my problem, I detached the electrical connection to the ISV-very interesting.
> The engine really bucked at idle.  Is there any preventive maintenance I can
> do to make sure my ISV will continue to operate?  It seems from the replies I
> received that a lot of people have had problems with their ISV.

Yup.  Take it off, make up a harness using two 3mm male spade terminals opened 
up slightly, apply 4.5v to 6v on and off to the terminals to bang the actuator 
up and down, and spray through some carburettor cleaner.  Bosch's instructions 
have an underlined comment that the plunger/disc should _NOT_ be touched with 
any implement.

-- 
 Phil Payne
 Committee Member, UK Audi [ur-]quattro Owners Club