Nissan Repair: 02 Nissan Xterra SE S/C - Engine Service Soon lamp blinking, nissan xterra, oxygen sensor

Question
Hi Calvin, I have '02 Nissan Xterra SE 3.3 S/C. I noticed my "engine service soon" blinking only few times two days in row at exact same place where I was driving uphill on the freeway about 60-65miles.  I notice a few pinging sound right before this lamp started blinking, it only blinks a few times and have not noticed otherwise the past two days.  The only other thing noticed was my engine idled rough just a few seconds during a stop at a red light.  My gas was tighten so could it be my emission control?  If emission control malfunction, would this be an expensive repair?  Terence

Answer
Hi Terence -

Seems like the oxygen sensor to me. The best thing to do is to take it to someone who has a diagnostic connector. That will retrieve the code and you will then know why the service engine soon light went on. There are hundreds of sensors throughout the engine that connect to the computer. if any one of them receives an error code, it will turn that light on. So, best thing is to find out what is causing that light to turn on, and we can take it from there.

Let me know -
aloha
calvin