Recently I have run into a strange overheating problem. Daily driving is not really affected but everytime i take the Supra out on the interstate and get back into town it overheats at the first stoplight. I mean the heat goes up quick!!! If i turn the car off and then back on again it drops to about halfway which is even stranger. it almost seems like the thermostat isnt opening until I shut the car off and back on again. Does the Supra use a simple thermostat system or is it electronic? Any similar problems from anyone here?