94 jetta w/ replaced motor...

I have a check engine lite problem...car runs great, but milage poor....motor was replaced by previous owner.....and air bags have been deployed, but never restuffed.....I'm guessing chk eng. lite could be one or more of several things.....I have located the test terminal to retrieve the codes beside ashtray....however, I'm not sure which wires I jump out to retrieve the codes via the chk eng. lite. any help would be greatly appreciated....Thanks so much!
Steve
:banghead:

go down to Jetta GL trouble code ECU retrieval and check out Boschmans entry.