Originally posted by Kremithefrog:
rvoth, did you have a check engine light? or just routine replacement? i have gotten CELs every couple of months for the sensors and will do them soon. what does 26 ft lbs equal in hand tightening terms?
No check engine light on my 95 V6 Contour. My sensors were a pasty white. As with spark plugs, this indicates contamination from either a lean burn or an overheat. (My water pump broke and my engine had been misfiring).
The front O2 sensor is easy to reach. Remove it and look at it. If it is a nice toasty brown, then don't worry about them.
You can also test the sensor by attaching a volt meter to it and applying a torch to the working end to burn away all the oxygen. You should get a voltage reading. Sorry, can't remember exactly what it would be, but likely either 3.5 volts or 5 volts.
If you have more than 100,000 miles on the car, however, replacing the O2 sensor may be something you should do anyway. I consider it a normal maintenance item because the computer is so dependent on the reading to judge how much fuel to give the engine.
- Randall
