I was reading in another thread about concerns someone was having with a 85 C4.
One reply to the OP was to make sure the check engine light came on when the car was started and then went right out afterwards. This got me to thinking, the short time I have had my 87 C4 I have never noticed the check engine light to come on and go off in this manner. Should it? The car runs great with no issues at all?? All I see is the security light when I open the door I think.

Thanks

 

Yes
Should come on with Ign and go off after engine fires up
I would start by checking the bulb

 

if you turn the key to the RUN position without stating the car, the CEL should light up and stay lit...then go out when you start the car