Why Does My Car Overheat While Idling?

One of the most common causes of an overheating vehicle is a problem with the coolant system. This can include issues with the radiator, fan belt, and water pump, all of which work together to ensure your car’s engine doesn’t heat up too much and damage itself and other components of your vehicle. 

The most common cause of overheating vehicles when idle is a damaged radiator fan. When driving, air passes through the engine, keeping it cool; however, when you are idling, your vehicle is not moving. Without the fan’s functionality, no air flow passes through the engine, so it overheats. 

Your radiator fan may not be functioning because of a faulty fan relay. If the relay that tells the fan when it should start blowing is not functional, the fan will not activate to cool the engine. 

Coolant and other fluids, in addition to a radiator fan, are essential to keeping your vehicle from overheating. If you have not replaced your vehicle’s fluids lately or your car has a leak, this can lead to low fluid levels. Without proper levels, your engine is prone to overheating and blowing a gasket, which can cause serious damage to the engine. 

Your vehicle has a built-in thermostat to monitor the engine’s temperature and ensure that the engine remains cool and functional. However, if the thermostat itself is faulty, it may not read your engine's temperature correctly. This can prevent the vehicle from enacting cooling methods to keep your engine at the correct temperature.