Its possible the heater in the sensor has failed but the sensor is still operating, just taking longer to start working (the heaters are there to get it into closed-loop control faster). If you still pass emissions and dont wanna fork out I'd leave it, if you want to investigate further you will have to find the pinouts for your sensor (all seem to vary) and test the heater circuit to start with.
J
Are you sure its the 02 sensor light? They dont normally have a light of their own, they fall under the normal check engine light.
Also, once broken the heater circuit will remain broken, though the sensor side will work after a delay, so a failure would still be flagged the whole time.
JMotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.