oil filler-cap effect on idle--how much?

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

In message <l03110701b04214451c44@[206.106.147.12]> Phil and Judy Rose writes:

> I went searching for a leak as suggested--actually just poking around
> briefly here/there with propane and turned up nothing. However--lo and
> behold--when I  re-tested (remove) the filler cap, the engine this time did
> indeed stop--pronto! Only difference this time is that perhaps the engine
> was hotter than before. Is a well-warmed engine likely to give a more-valid
> (oil-filler) test than when not-so-hot?

Yes.

> Then, while idling around (mow the lawn my SO says!), I pulled the ISV
> connector off, and the idle speed increased by a couple of hundred rpm (to
> about 1000), which I assume indicates we have a working ISP? But when I
> reconnected it, there was _no_ effect (reduction) on idle speed even after
> waiting 20 or 30 seconds and even pulling a bit on the throttle to help
> "reset" things. I shut down and restarted, and the idle was back to its
> usual 750 rpm. Is that normal idling speed behavior for this sequence of
> events ('89 100)?

Yes.  Once the ISV circuit has been broken, the controller will not attempt to 
operate the valve until the ignition has been switched off and on.  A point to 
bear in mind when putting a meter in the circuit.

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