I've checked the gas cap, air filter, and coolant levels. All of these are fine, so could it be from gasoline with a high level or grade of octane?
Check engine light stays on, but car rides and operated fine??????? not gas cap on 2007 Chevrolet Cobalt
Auto Zone free code check might help
99℅ of the time this is caused by over filling of your gas tank when at pump don't keep pumping your gas after it clicks before you do real damage check engine light will go off after a few fill ups without counting to overfill