hey guys my 89 cavalier is acting up and i had a check engine light that went on but went off after 10 minutes and hasn't come back on in a couple days. My friend who is a mechanic (lives in another state) showed me how to use a paper clip to connect the diagnotics connections or i guess you would call them ports. It would then flash the code. He has done this on my 87 camaro. He doesn't seem to remember which ports to put it in. I am poor right now and don't want to pay $60 to have someone scan it. so if someone has ever heard of this and can tell me how to do it i would be very greatful.

thanks
Tom