Hi, my CEL is on and says it's the rear heated O2 sensor that isn't working well. I don't know why but the light appeared and disappeared a few times but now I think it's enough and I bringing it to the garage. They estimated $125 for replacing the sensor. What do you think? Should I buy the book and do this job myself or let them do the work (since I don't have any mechanic experience)? How much is the sensor? Any advice would be appreciated.

 

I got the sensor for $90 from NAPA, a manual for $15, and it was easy to do. In the end, you're better off doing it yourself...and the manual will be useful in the future.

 

I purchased the rear O2 sensor from Courtesy Nissan. Including shipping the cost was $65. Received the sensor in 2 days after ordering by phone. Went to Auto Zone and used their free rent a tool program for a special O2 socket wrench. (Need to have this socket for the rear sensor) Took about 5 min. to replace.

 

I have the same code (0707) coming up every so often. I reset it and it comes back anywhere from 3 to 15 days.
From what I have read here, this sensor doesnt affect performance. it just monitors the Cat. convertor.
I have heard of people cleaning the sensor with alcohol, or break cleaner....I havent tried it, but I guess I will when it is not freezing outside.
Good luck.