The guy at Autozone said that they can generally read the codes from any OBD-II system, which would be any 1996 or newer model, but they don't have the equipment to test older systems.

What happened in my case was the car was (stupidly) run out of gas. The light came on then and has been on since. I'm taking a wild guess that the O2 sensor may have been damaged somehow, but do not know for sure.

The car runs and drives fine, but if there is a problem I want to fix it.

Thanks,
Dean