just bought this car and was told it was overheating ....haven't checked it myself because of fear that it might blow the headgasket....how can i check to see whats wrong with it..the previous dealer said he removed the thermostat to see if it would fix it....he then said it still overheated but took longer to do it....theres not any water in the oil or extreme pressure build up in the rad...any info would be greatly appreciated