I need the second O2 sensor for a 96-97. The one right after the cat. I'd like the whole wiring and harness. Thanks

 

autozone.. probably 50-60 bucks.

 

I was hoping for a used factory one. I have a generic in now and am having problems with it.

 

hmm, i cant see why it wouldnt just be a standard narrowband sensor? If you want a used piece, i suppose salvage yard shopping or FM salvage is your best bet. I like the URG network and there was another that was pretty good, a google search should get you a URG search engine.

 

I can't explain it but I allways have a check engine light now and my A/F will dip into rich for no reason. I just figure if I can get a OEM one I wouldn't have to worry about it. What's URG?

 

As far as I understand it, the second O2 sensor has no influence on mixture control. Its purpose is simply to sit there checking to see that the exhaust mixture always appears to be lean, as this is an indirect method of verifying that the catalytic converter is operating properly. The most it can do when it detects a problem is throw a CEL for catalyst efficiency. (something in the P042x range)

If you are running rich under cruise, I would suspect either the forward O2 sensor, the MAF sensor, or the fuel system. Note that a genuine rich condition could result in a secondary CEL for the cat or the rear O2 sensor, but in this situation it would be a symptom of the rich condition preventing the cat from doing its job, not necessarily a failure of the cat or the rear O2 sensor.