I just had a rear o2 sensor installed, after I left the shop my service light came back on. So I brought it back and they ran tests and confirmed that the o2 sensor they just installed is shot.
Do you guys think it was just a bad nissan part?
The mechanic says he's never had a computer burn out sensors before but said anything is possible.
Could this be the begining of a bigger problem?
any advice would be greatly appreciated, thanks

I had a code dealing with O2 Sensors and it turned out I needed new spark plugs. Reason being the sensor picked up a bad reading and told the computer so it gave a O2 sensor fault. That doesn,t always that sensor is bad but that it just is reporting that something it read did not fall within specs. It is possible that a bad part was installed but not highly likely.

Same happened to me... after I left the Nissan Service, I went racing and the check engine light came on after the first race. When I brought it in the next day they said it was the one they just replaced.

My Service Engine Light came on and I took it to the Dealership. They tested it and showed me the results. The rear O2 sensor was reading nothing. Flat Line. The weird thing is that I have an Air Fuel Gauge installed and that taps into the Rear O2 Sensor and it is reading fine. Anybody know what is wrong??