Re: 94 90S stalling

[Chris Newbold <cnewbold@transarc.com>]

Benjamin Kwan wrote:

> The mechanic has cleaned out the ISV and checked for vacuum leaks.  After
> cleaning out the ISV and re-installing it the situation has become worse.
> Are there any cases where the ISV has to be replaced and not just cleaned
> out?  Thanks, again to the listers who replied to the last message.

Did the mechanic check for trouble codes on the ECU? They may provide a clue
about what's going on.

After a bout of unstable idle and stalling, the dealer replaced the
ISV in my 1993 90. Apparently Audi had a "bad batch" of ISVs, and the
criteria for replacement was the date of manufacture for the ISV.
I believe this only affected 1993 and earlier cars, though.

Also, the defective ISVs failed rather quickly; mine died within 12k miles
or so... Makes me doubt this would be your problem. More likely, yours just
up and died.

If the car has < 50k miles, Audi should replace the ISV under the mandated
5/50 emission warrantee.

-Chris
1993 90CS 70k miles