Does anyone know if you can check an O2 sensor with a multi meter at the connector with the connector unplugged and tell whether or not the sensor is bad ? I have a 97 Olds Bravada with 4.3L.
Thanks

Hi,

The O2 Sensor carries different voltages to the ECM.
Do a search on google "GM O2 sensor"
If you have a diag tool and are getting code 44 O2 error, you may want to check you MAF Sensor, they work closely together.

Sorry I cant be of more assistance

Thanks Big Al I will check that out. Actually the code I'm getting is P0507 Idle Control System HIGH RPM. I have tried almost everything just thought maybe the O2 sensors might be sneaking in the back door with out showing up as DTC's.

There are things you can check with a meter but if you have a check engine light on it would make it easier to help knowing the code.

Things you can check;
check 5 volt reference circuit.
check ground circuit.
check the heater power circuit.

Codes 44 and all 2 digit codes do not exist anymore since 1995 model year. They are all a 4 digit code now like P0121 and so on.