My thermostat was replaced two days ago and now the temp gauge constantly goes up and down between midpoint and hot. It hasn't gone quite to H so that the engine light comes on - it just hovers and doesn't settle anywhere. Could the thermostat be malfunctioning? What else would cause this? The head gasket is not blown. The radiator is full. The coolant is full.
Apr 8, 2009 at 11:04 AM