O2 sensor readings

[Brian Devlin <bdevlin@stanford.edu>]

snip
>try new plugs, cap, rotor, maybe air filter.
Done recently, except the Air filter (K&N, about 1 year old).


> > O2 sensor is a generic 3-wire, with less than 10000 miles, no vacuum
> > leaks (I think).
> >
> > The data:
> >
> > engine cold, idleing or driving: 0.5 volts (I assume this is a bogus
> > signal generated before the sensor warms up).
> >
> > warm, idleing: wanders from 0.2 to 0.7 volts, occasionally 
>outside this range. * that's good
> >
> > warm, throttle closed, 1000-2000rpm: 0.7-0.8 * weird.  you mean 
>if you give it gas the voltage goes up and stays up?  That's running 
>rich.
> >
> > warm, throttle closed, >2000rpm: 0 * and that would be lean. 
>both of these are wrong, should still wander...
> >
> > warm, driving: wanders like the warm idle, but stays closer to 
>0.5. * that is good.
> >
> > full throttle acceleration: 0 at low rpm (2000) rising to 0.7 at high rpm
> > (4000).
> > Does this mean I'm leaning out at high RPM? Time for new filter? 
>* I just checked Probst to make sure... higher voltage is rich, that 
>is what WOT is supposed to do, open loop forced slightly rich.
The voltage change seems a bit slow, but I guess I should try it 
uphill to see whether I can build up to 0.7 at lower RPM.

>except for those two middle readings all seems ok.  How do you get 1-2k
>and > 2k rpm with the "throttle closed", btw?
Thats decelerating (Graydon-I usually idle at 700-800). I'm thinking 
the change in mixture at 2000 rpm has something to do with the 
jerking, but what could be the cause?


BTW, I thought oxygen made voltage, so 0.7 would be lean?

>--
>Huw Powell
>
>http://www.humanspeakers.com/audi/
>
>82 Audi Coupe; 84 4kq; 85 Coupe GT