Alright, so I just bought a 1985 Firebird Berlinetta two days ago. It's my first car, so I'm still just learning the mechanics of it. It's a great car really, runs amazing, very minor rust all all (previous owners did a lot of rust and body repair with bondo/duct tape hahaha), the paint is in rough shape, some bondo still showing here and there, plus a strip of duct tape or two, but that's all an easy fix. Over all in excellent condition considering what I got it for.

Now when I originally looked at the car, the check engine light wasn't on. But when I drove it home, it turned on randomly. Was on for a while too since I got it home, but haven't had any problems with the engine whatsoever, it ran great. So I have no idea why it was on. The Air compressor isn't hooked up and there is no belt on it currently, so I don't have A/C but that's not a big deal. I originally started to think that's why it was on, because the AC compressor wasn't hooked up.

But just this morning when I went to start it up, it started up fine, then I threw it into reverse (automatic), the engine just died on me. This took me by surprise because the engine was running just fine.

So I was like "alright..." threw her back into park, turned the ignition off and turned the car back on, started right back up. Only this time, the check engine light was only on during the initial start up, and turned off right away. So now the check engine light is no longer on. Now my first reaction was "did whatever was making that turn on just fix itself or something?" Of course, cars don't just "fix" themselves.

It still runs and drives great, just doesn't have that check engine light on it anymore. I have no idea what to make of this.

Thoughts? Ideas as to what was going on?

 

Use the paperclip method and read the codes out. It's documented under the Tech Section.