O2 Sensors?

[KJB]

I have a '96 Explorer with a 4.0 and it has 123,000 highway miles. The Check Engine light has come on and the dealer checked it out and told me the oxygen sensor needs replaced. I checked along the exhaust system and found what look like three O2 sensors. How expensive are these suckers and where can I get them? THANKS!

 

[Phantom]

There are actually suppose to be 4 of them but I haven't looked to see. You can get them anywhere for about $50 a piece. Do you know which one is bad? You can check them if you have a meter but I'll have to look up the proper spec numbers though.

 

[KJB]

Phantom, that would be great if you could get the specs., it would sure be less expensive to change the faulty one rather than all of them. THANKS!

 

[Phantom]

According to the Chilton manual:
1. Disconnect the HO2S.
2. Measure the resistance between PWR and GRD terminals of the sensor. If the reading is approximately 6 ohms at 68 degrees F, the sensors heater element is in good condition.
3. With the HO2S connected and engine running, measure the voltage with a Digital Volt-Ohmmeter between terminals HO2S and SIG RTN(GND) of the oxygen sensor connector. If the voltage readings are swingly rapidly between 0.01-1.1 volts, the sensor is probably okay.

Now how you pull off #3 is beyond me but I'll be giving it a shot Monday. I could only find 2 oxygen sensors on my 96 so I guess Chilton needs to update their manual. I'll let you know how it goes.