Finding/Reading "Check Engine" codes

["Sean Ford" <sean@nwh.org>]

Please forgive me, but I've lost the message that someone sent on how to
read the "Check Engine" warning codes.

It seems that my "Check Engine" warning is displayed whenever the car sits
at idle for about 2-5 minutes. It will go out once the car is back
underway, however, the coolant and oil temperatures never rise (so it's not
overheating). I'm now convinced that it had nothing to do with the car wash
incident that I wrote about last week, it only happens with sitting at idle
and the car is sufficiently warmed up. I wonder if this has something to do
with the rocking idle; hmm?

Anyway, could some kind soul send me instructions (and please, write to me
as if I'm an idiot, since I am in this respect) on how to determine what
the "Check Engine" code is? I'd love to be able to narrow this down. Thanks
in advance.

Sean Ford
sean@nwh.org
Newton-Wellesley Hospital
Newton, MA  02162 (USA)
'92 Audi 100CS 5spd  17K miles (and counting!)
'89 Suzuki Katana 600 14K miles (and hibernating)