O2 sensor

About how ofter should one change the O2 sensor.
My car has 307 vin y engine and about 20k since i last changed it.
The CEL has flashed on a few occasions briefly, then went out when the car was first started in the morning. Other than that, no CEL.
There were no codes stored when i checked.

Thanks for the input

Al :smokin:

A failing sensor is rare and it is rare that the MIL will come on because of the sensor. More likely, there is an issue with the air/fuel mix and the EGO sensor is relaying this to the computer.

If the engine is not running rich, expect 50k miles out of the typical EGO sensor.