Causes of an Overheating Car

Overheating can seriously damage a car's engine if left unchecked. Although overheating simply means that a car's engine temperature exceeds normal operating temperatures, the causes of overheating are varied. What follows is a brief list of some of the most common causes of engine overheating.

Faulty Radiator

  • A car that overheats will often have a faulty radiator. A radiator is responsible for cooling hot engine coolant that picks up heat from inside a car's running engine. A radiator "radiates" the heat from engine coolant out into the outside air. A faulty radiator loses its "radiating" effects and allows engine coolant to become overheated, thus rendering it ineffective at adequately cooling and engine.

Faulty Water Pump

  • A faulty or malfunctioning water pump prevents adequate engine coolant flow and can cause a car to overheat. A water pump serves to pressurize and propel engine coolant throughout a car's engine and radiator to increase the heat-reducing capabilities of engine coolant. A faulty water pump loses its ability to adequately pump and propel engine coolant, and can cause a car to overheat.

Coolant System Leaks

  • A leaky engine coolant system reduces the level of circulating engine coolant, which increases engine temperature and leads to engine overheating. Radiators, water pumps, and coolant system hoses and seals--all of these coolant system parts can develop leaks, which can result in low coolant levels and engine overheating.

Faulty Thermostat

  • A car thermostat regulates the flow of engine coolant. A thermostat is a heat-sensitive valve that opens when a car engine reaches a set operating temperature and closes when a car engine is cold and warming up. If a thermostat gets stuck in the closed position, coolant will be prevented from reaching the engine, which will quickly lead to engine overheating and potential engine damage.

Low Engine Oil Level

  • Engine oil, in addition to lubricating an engine's internal parts, helps to keep engine operating temperatures reduced by eliminating friction within the engine. If engine oil levels are low, friction and heat build up inside an engine, a condition that causes increased engine operating temperatures and can lead to engine overheating.