My CEL was on with a P0510 error code for a pre cat O2 sensor. So I reset the CEL and it comes on again, I ordered an O2 sensor from Pelican Parts, it arrives. I am out for a Sunday drive and the CEL goes out?

I have never seen the light go out on its own before, does this mean I don't need to replace the O2 sensor?

The bulb is not burnt out.

Tried search feature and could not locate the answer.

 

on my audi the 02 sensor cel does go off by itself. on the 993 the 02 sensor cel comes on after driving the car like a granny. if I drive it in a spirited manner no 02 sensor problem.
I recommend driving it hard then check obd2. good luck.

 

Some CEL's go out automatically after a couple starts.

 

Does this mean the fault is no longer or that it assumes you will check and correct?

 

O2 sensors fail intermittently at first, so the CEL detects the failure, then clears when it detects the temporarily "healed" sensor. Replace the sensors and you will solve the problem.