what should DMM read at WOT ???

[Huw Powell]

> I picked up a Digital Multi-Meter today and hooked it up to my O2 sensor so I
> could check A/F ratio on the fly.  At idle it averages around .5v which is
> normal/correct I believe, 

yup, it should *always* fluctuate up and down around .5 v while in
closed loop.

> up to WOT it increases to around .6v - .7v or so.
> At WOT it goes to .01v - .02,  is this what should be happening or is there a
> problem I need to address?  I switched the wires around on the full throttle
> switch and even touched the wires together but it never went to .9v and I am
> thinking it should.  If there is a problem what should I check next?  My car
> is just CIS injection not CIS-e if that matters.

trying to remember here - if the OXS actually senses oxygen and puts out
a voltage proportional to the amount of it in the exhaust, running rich
would yield a low voltage, and that's what the car is supposed to do at
WOT.

You're really measuring the wrong thing anyway, a much better indication
of what is heppening is obtained by tracking the duty cycle of the
frequency valve, which is conveniently tapped at that "connector that
goes nowhere" behind the intake boot.

-- 
Huw Powell

http://www.humanspeakers.com/audi/

http://www.humanthoughts.org/