Hi all,

I have a 2003 Civic HX (not under warranty anymore) - just turned over 40,000 miles. I recently had my check engine light come on. Took my car to the Honda dealership for a diag. and they said my primary O2 sensor needed to be replaced.

So instead of paying them $400, I bought the part myself ($200 for a Bosch sensor) and replaced it. I had the code reset, but after driving 36 miles, the engine light came back on. I took my car to another mechanic for the diag. and am receiving a P1164 error (Air/Fuel Ratio (AF) Sensor (Sensor 1) Circuit Range/Performance).

It appears this error still relates to the O2 sensor, but I don't know. Can anyone shed any light on this?

BTW - after replacing my O2 sensor, my gas mileage has gone back up to it's normal level of about 40mpg.

Thanks!

Chris