Q: I have my Service Engine Soon light on. The dealer said it will cost me 280.00 to raplace the O2 sensor Theres two sensors, but the one in the back is the most critical one
A: Your car should still be under warranty unless you have too many miles on it. You can change it yourself with an O2 sensor socket. You can get them at most parts stores. You should get the Nissan O2 sensor though. The aftermarket ones have been known to not work well.