Is there a way to check each O2 sensor, from the harness, with a simple digital volt meter. Is there some specific resistance I should check for, or is it impossible to do since the sensors need to be heated, which means the car running, which means burning my hands off!
Thanks <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

I didn't try this method on an O2 sensor, but it worked on my TB. Get two alligator jumpers (a black one for gnd and a red one for HOT). Hook the jumpers up to the meter. Clamp the black jumper to a clean metal surface. Clamp the red alligator jumper to a small sewing needle or sewing push pin. Push the needle thru the insulation of the wire you want to measure without having to strip the insulation at all. It worked really well for me when doing my TB mod.

 

I didn't try this method on an O2 sensor, but it worked on my TB. Get two alligator jumpers (a black one for gnd and a red one for HOT). Hook the jumpers up to the meter. Clamp the black jumper to a clean metal surface. Clamp the red alligator jumper to a small sewing needle or sewing push pin. Push the needle thru the insulation of the wire you want to measure without having to strip the insulation at all. It worked really well for me when doing my TB mod.

 

The o2 sensor is basically a fuel cell.
You need it to be at operating temp and
have some exhaust running by it, to see
anything but zero volts. It has a pretty
high output impedance, so an old-style
analog VOM won't do (it messes up the
output fidelity) and the resistance
should read very high.

Just look at the volts with the car running,
should be bopping around between 0 and 1.0V
(ideally spending most of its time between
0.3 and 0.7V).