Hey, my mom's got a 94 Deville (which is pretty much the same as a Seville) with that digital cluster thing like your car has. The message center, at the bottom of the cluster (tach, oil life, systems check, blah blah), usually tells you if something is going wrong (if the service engine soon light doesn't come on). It seemed like her car would show that "Engine Coolant Hot" and "Engine Hot" message when the anti-freeze needed changing, but shouldn't it say "Change Coolant" if that was the problem? I mean, its a Cadillac, go figure. It could just be that your coolant temp/engine temp sensors are bad and making the car act like its really wrong. I would bring that up to Cadillac when you take it back. Let me know how things go. My e-mail is
[email protected] if you want to get back with me.