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RE: ISV Questions, 1988 90q (longish)

Kirby wrote:

	>Last week I was having some routine service done and complained
that my 
	>idle was running at 1200 rpm (warm, w/o AC) and hunting.  My
mechanic du 
	>jour hooked up a digital multimeter into the ISV circuit and
	>the %CO screw (in the metering head) until his meter read a
sequence of
	>current values (he said, I didn't check the hookup) that had a
	>2.5 mA mean.  He suggested I clean the ISV and reset the
current as 
	>required.  He said, reasonably enough, that the jittering
	>indicated a properly functioning oxygen sensor.
	>I haven't found anyplace in my Bentley documenting this
approach to
	>adjusting the %CO.  Has anyone heard of this "shortcut?"  Is it
	>perhaps in VW CIS tuning?

I wouldn't trust anyone who adjusts %CO not using an exhaust gas
analyzer. I also doubt if the oxygen sensor has any effect on ISV valve.
That's what the frequency valve is for. I may be wrong, but that's my

Aleksander Mierzwa
87 Audi 5000CS turbo (mine)
88 Renault Medallion wagon (mom's)
91 mountain bike (just in case both cars broke at the same time :-)