Hmm where to start.....OK, basic problem, car can run up to over 240*, replaced fan temp switch, tested relay, threw in 180* thermostat. Now, heres the real mind blower, when the fan switch harness is unplugged, the fan is not supposed to run unless you ground it with a jumper wire, but mine does. So my solution, I leave it unplugged and run it that way, but it sends my computer false crap and the car runs rich as hell and just plain old horribly and throws coolant circuit errors at me. Now, plug it back in and errors go away, but temp sky-rockets and fan never comes on. Where is the problem? Im not an electrical system phanatic so if yous could give me some pointers I'd be very happy. BTW its a 2.8 (yes, a V6) '87 Firebird.