Originally posted by: Chiboy
My car has 2 Sensors, the second located under the car. Now I need to replace that & all should be well. I looked every where for No. 2 rear sensor. I guess I have to go to the dealer
Exact location:
UNDER VEHICLE, CENTER, BELOW SEATING AREA, NEXT TO CATALYTIC CONVERTER, MOUNTED ON EXHAUST PIPE
Well, if you go to autozone and get a code again for an O2 sensor just identify which one it is. It's entirely possible that you replaced a good front with a new front, needlessly, but you could hopefully get that money back, although it may have gone some time anyway
The rear one is actually easier to find than the front one - at least on my maximas. On my 93 sentra the front O2 sensor was easy to find. The rear one is underneath the car. You'll probably need to jack it up/ramps/drive on a curb, but if you look underneath about half way to the back of the car you will see it sticking out of some of the exhaust work down there.
Then, assuming that you've changed the right O2 sensor, just disconnect your negative terminal and go enjoy a night of beer, and come back, plug it back in and see if the code is gone.
Once you've found it you may need an O2 sensor socket to get it off, if you don't already have one. Autozone lends them out, or you can buy a new one for about $15 from autozone.