Find a Pep Boys store. They diagnose it for free. I had it in my 98 civic and they diagnosed it for free. I went to some Gulf Gas station near where I live and they were going to charge me $100 just for a 1 min diagnostic!!! All they had to do was plug it in the computer port and then BOOM! the code would be there. So I ended up going to Pep Boys and they did it for free.

P.S. GULF Gas station in Herricks Road, in Long Island NY. Near Nathans...THEY SUCK!!! buncha scammers!