Why is my car overheating

There are a few possibilities. First, be sure there is plenty of coolant in the cooling system. A 1:1 ratio of water and antifreeze is normal, but if necessary, pure water will do temporarily. It is always best to use distilled water to prevent minerals from building up in your cooling ports and hoses. Have you seen any water on the ground underneath or beside your car? That could indicate a leak. If your coolant level is low, your temperature gauge/coolant light might not function because the coolant temperature is what is monitored.

If coolant level is ok, check to see if your heater is working (getting hot). The same water that cools your engine is circulated through a heating coil. A fan blows air through it and into the passenger compartment. If the heater isn't getting hot, and the coolant level is good, that could indicate the water pump not working or a thermostat that is stuck closed (see below). Driving without a functioning water pump will seriously damage your engine.

Your car has a mechanical fan attached to the motor, but it also has an electric fan to assist in cooling the engine. Anytime the engine gets above normal temperature that fan should come on. It might also come on when the A/C is on or when idling for an extended period. The fan is easy to see behind the radiator. You an hear and see if it is running.

To control water flow, there is a thermostat on the engine connected to the large (1½" - 2" diameter) upper radiator hose. It closes when the water in the engine is not hot so the water remains in the radiator long enough to cool it. Then when the engine water gets hot, the thermostat opens and the water in the engine is replaced with the cooled water. If the thermostat is stuck closed, your engine will overheat quickly. If it is stuck open, the water will not stay in the radiator long enough to be cooled and your car will overheat slowly, but when it gets overheated, it will never cool.