autozone and advance can't check an OBD1 code for you, they dont have the right scanner, OBD1 scanners are ridiculously expensive if im not mistaken. i went and got mine checked on the DL for $25 but they usually charge almost $50 for it on a regular basis. im going to assume yours is OBD1 or 0 so you will either have to take it to a good shop and pay out the a$$ or do the paperclip. its super easy to do the paper clip and there are 1,000,000 forums with lists of the code readouts. and its important to put the paper clip in and then start the car. then the CEL will start to flash