I have a 95 cadillac sls the s.E.S light comes on while engine is cranking, but is not on with key on. Car idols eradic and stalls when stoping rpms are eradic, can I scan codes with out ses light on when key is in on position
Turn the key to on, and press off and warmer. All codes for all modules will display on the info center. It sounds like you may have no codes, or codes that are irrelevant to the symptom, but may have an ISC(idle speed) motor issue.