Q: Whats wrong if my car went up to the h for over heat then went back to c then back to h over heated cut off while i was driving

Hi there. If you noticed the thermostat on the dashboard is going from cold to hot, it is possible that the thermostat on the radiator is not opening when it is supposed; which can cause an overheating problem. However, it is also possible that the water pump, heater core or other cooling system component is faulty and will require service. I would recommend having a professional mechanic come to your location and complete a car is overheating inspection; so they can pinpoint the source of your overheating problem and recommend the right repairs.

Overheating can be caused by a number of things such as low coolant levels, a faulty thermostat, a clogged radiator or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. You may also have a water pump that is beginning to fail. Water pumps often times will begin to produce a bit of a whining sound when they are starting to fail. A common problem also associated with this is the water pump may begin to leak around the water pump shaft due to the seal being damaged. In addition to leaking around the pump, you may have a leak elsewhere in the cooling system coming from one of the hoses going to or from the radiator. Lastly, you may have a failing cylinder head gasket allowing coolant to leak from the water passages into the cylinders resulting in the coolant being burnt in the combustion chamber with the fuel. If this is the case, you may also notice a bit of white smoke coming from your exhaust which is a product of the coolant being turned into a steam like vapor. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.