What Problems Could Cause a Honda Civic to Run Hot?

A lack of coolant will make the vehicle overheat. Coolant absorbs the heat generated inside the engine block. It flows through the small metal tubes of the radiator, and is cooled by blowing air before it returns to absorb more heat. Leaks in the rubber hoses and radiator -- or internal engine problems -- can cause your vehicle to lose coolant. Check the coolant reservoir -- and open the radiator cap -- to make sure coolant is visible in the radiator.

A small thermostat is located just inside the joint pipe of the radiator's rubber hoses. The thermostat blocks the flow of coolant until it reaches a certain temperature. When operating temperature is reached, the thermostat pops open and allows coolant to rush into the engine. The thermostat can stick closed at times; this will cause the engine to starve for coolant.

The engine powers the water pump with a drive belt found on the face of the engine block. The belt powers a turbine on the inside of the pump. The turbine is responsible for making the coolant flow through your system. The bearing on the pulley to the water pump can sometimes fail, and the turbine can seize with old age. Without coolant flow, your engine will overheat.

The radiator is just behind the grill of your Honda Civic. It is a series of small, metal tubes that the coolant is forced through before circulating back to the engine block. Air must flow through these metal tubes to take away the heat accumulated by the coolant. An electrical fan located behind the radiator ensures air flow when the vehicle is stationery. The vehicle will overheat in traffic if the fan fails.

The radiator tubes can become clogged. Coolant can accumulate sediment during its flow, and clog narrow passage ways. The heater core is a smaller radiator inside the engine compartment near the front passenger seat. It is responsible for heating the interior of the vehicle, and can also clog. Restricted coolant flow will cause overheating.