2002 pontaic grand prix wierd issue
 

ok heres the problem... the light on the dash that sais "temp" is on from the second you start the car the fluid is topped up and there is no air in the system.while this "temp" light is on the car works really bad like it is running off 4 not 6 ,runs really rough and has no power what so ever will not go above 4k on the tach. now heres the messed up part every time i take it to get someone to look at it for some reason that day the "temp" light works fine and the car works as it should.does this make sence to anyone at all ?

RE: 2002 pontaic grand prix wierd issue
 

sounds like a short. trace the wire from the coolant sensor ( mounted on or around your thermostat housing) make sure its plugged in. your computer has a safety programmed into itthat wont allow the engine to excedea specific rpm as a safety device. it might even kill some cylnders to keep the heat down