Any ideas? Thought if a sensor went bad it stayed bad...checked my gas cap and always tighten to 3 clicks...

Not enough $$ to bring to dealer for a while....

Anyone on why it would be on, off and now back on again?

just past 60K

 

ecu takes the previous 26 (I think it was 26...it's in the factory service manual) engine starts (engine must go from cold to normal) and decides on what to do. If a sensor goes bad once in a very long while, then that's your problem
when i cleaned my engine, i musta got something wet (that wasn't supposed to be wet). My SES was on for 2 weeks, then went away. Water musta dried up.
Jae

 

Sounds like you have a bad o2 sensor.

I've had that happen to me a numerous amount of times.