side1out joined the community
Wife's car (RX400H) has the same issue. I don't understand how blasting the heat has a significant effect on the coolant temperature. Does a head gasket leak itself cause a car to overheat or is it due to loss of coolant? Coolant levels (radiator and overflow) are fine so how would a head gasket cause overheating in this case? By the way, the car's first issues were shaking at 40mph and a check engine light related to cylinder mis-fire. Blue Devil treatments were done but not effective.