O2 sensors

Hello all! Just ran up on this site after searching around for parts for my s-10. Need somebody to explain to me why it's such a hard thing getting this resolved! I have a 1998 s-10 ext. cab, v6 4x4 @ 80,000 miles. Check engine light has come on again ( had this serviced 3 years ago) and it seems everyone wants a arm and leg just to look at. I stopped by parts store where they read codes for free. Again after extensive research I have finally gotten to the point where I have the info needed for getting part but it seems I don't have ALL I need to get them. Here's what I have, codes P0135B,P0147B & P0155. All are under the same heading: O2 sensor Heater Circuit Malf. (bank1, sensor1-bank 1, sensor 3-bank 2, sensor 1) Now it seems that as I look at various auto part web sites, it seem that all they list are 2 kinds (1 before Cat. Conv., 1 after). So if someone could help me figure out what I need to do it would really help. Oh and is it a very hard thing to change?? Again thanks for any info you can give.

some o2 sensor has two bolts holding them in and some just screw in, i would have to say the best bet would be to change them both and see it the engine light is still on and if so have the code read again

you need to replace your heated o2 sensor...it is after the catalytic converter it is very easy to do yourself and will save you about 100 bucks doing it yourself all you do is unscrew, unplug, then screw and plug. then to reset the computer simply dissconnect your negative batt. cable for 30 seconds and reconnect :biggrin:

Hello. I Have Never Seen 3 O2 Sensors Fail At Once. The Three Codes You Are Seeing Is For The O2 Sensors Heater Circuit. Before You Change These Expensive O2 Sensors Go Under The Car And Check The Wires Going To Each O2 Sensor. Disconnect The O2 Sensor At The Connector And Turn The Key To The On Position. You Will Need A Multimeter To Check The Wire Voltage. You Should See At Least 12v On At Least 1 Of Those 4 Wires. If You Dont See The 12v Then Your O2 Sensor Heater Circuit Has Failed. There Is A Seperate Circuit For The Heaters. Look At Your Relay/fuse Box And Look For The Relay/s And Fuse/s To See If They Work. I Bet That Is Your Problem. Like I Said I Never Heard Of 3 O2 Sensors Failing At The Same Time. If You See 12v Then Most Likely Your O2 Sensor Is Bad. Good Luck!