1995 Nissan Maxima......Could someone tell me if there is a difference in appearance of the front and rear O2 sensor. Was going to get my husband to replace the rear one, ECU said it was bad. So ordered one from Autozone and it is not the same. It looks completely different than the front. Are we looking at the right one? It's pretty much in the center underneath the car, right?
Thanks, Kerry

 

the one on the cat has two wires. maybe you bought one with a different wire config.

 

There are two precat O2 sensors (left bank, right bank) as well as the one after the main catalytic. The harness length is different on each.

 

I replaced the one on the cat yesterday on my car and I counted 3. the ones on the right and left cylinder banks have only 2.

 

Thanks for trying to help. All 3 on a 95 Maxima are different. I found pics at Courtesyparts.com and thepartsbin.com. AutoZone seems to only have the one for the right front $77, bit says they carry all 3. I just ordered one from the parts bin for the Rear O2 Sensor for $82. My local Nissan dealer charges $139 for them. Thanks again!

 

Kerry,

I just replaced my two pre-cat sensors.

* they do look different from the OEMs, but I think that they are the correct replacement

* They are different part numbers - theres a left one and a right one.

* I bought mine at autozone for 77 each, they work great for me.

Hope that helps.