I had this problem in mine, i checked the coolant, oil everything that i could think of. however if when your car is hot or overheating and you turn your heating on and its cold, it is your head gasket that is the problem.
Gavin, July 2008
it could be your thermostat. ur radiator cap . does the fan work on the radiator,need more info to be more precise . does it only overheat after 50 miles or so if it does thats an inefficient radiator. is ur heating in ur car bad that could point to an air lock in the cooling system or the water pump.