Re: Idle stabilization system questions

[paul.heneghan@bbc.co.uk (Paul Heneghan)]

From: Sdbigelow@aol.com

>My 84 5k unTurbo is idling at about 1300-1400, in park, hot. This is a new
>occurance, it used to idle correctly. I've cleaned the ISV (which was 
pretty
>good anyway, BTW) and am starting to look at the connections for the
>thermoswitch (which are grotty).
>Mr. Bentley sez to connect blah-blah meter to the ISV and check current. It
>appears that the blah-blah meter has TWO multi connecters on it. Can I just
>come in the back way with my lowly peon meter on the ISV connector while
>still connected and check current there ?

I would think so.

Here are some things to check.

Unplug electrical connection to ISV.  Do revs drop?

If they do, then ISV is OK and fault lies with controller or signals going 
to controller.  Maybe the controller thinks the temperature is very low and 
is idling high - check temperature sensor wiring.

If they don't, then either ISV is stuck open or throttle is stuck open or 
throttle bypass (large brass screw in throttle body) is loose and beginning 
to work its way out (very likely - has happened to me and several others on 
this list).

Good luck

Paul
paul.heneghan@bbc.co.uk
1984 Audi 80 quattro
1989 Audi 100 Avant