I'm trying to determine how many O2 sensors I have and whether they are heated or not. I have a '95 Cab AAH engine. Bentley's is not exactly clear on this. Is it 2 or 4? Additionally, will the OBD codes definitively tell me if an O2 sensor needs replaced? I know, I need to break down and buy the OBD I Vag-Com. Thanks.

 

check the exaust and count em' , heated, voltmeter can tell you if there bad too

 

heated O2 sensors mate HO2S

 

Heres some good info all about the o2 sensors, diagnosis, how they work, etc

http://www.aa1car.com/library/o2sensor.htm