read engine codes?

Anybody know how to trigger the Cavalier
to give you the engine codes?

I once had a '81 Firebird that would often junk
out its oxygen sensors and have associated probs.

I took it to a friend who was a mechanic, and
instead of hooking it up to a computer to read
the engine code, he just stuck a piece of metal
between two contacts in the "computer" plug.

Then he watched as the Check Engine Light
blinked out the numeric codes. (oxygen sensor
and mixture too rich) :cool:

I'm in a cruch, because I'm supposed to leave
on a 7-hour road trip thru the desert out here
in CA and I need to leave by mid-day tomorrow.
So any trick to let me know ahead of time
whether it's a serious problem or not would
be really helpful.

Thanks
Scott

Unfortunately, on new vehicles (1996 and up) now you have to scan the system using and OBDII compatible scanner. The old system was convenient. Not so anymore. You can take it to a garage to get it scanned. Leaving the gas cap loose will set a code. It could be as simple as that. Get it scanned. Good Luck.