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Reasons Your Car Overheats When Idling

Reasons Your Car Overheats When Idling

Reasons Your Car Overheats When Idling

In the summertime, car owners everywhere are familiar with the phenomenon of their vehicles overheating while they're parked or in very slow-moving traffic. But what causes this problem and what can be done to prevent it? In this article, we'll explore some of the reasons your car overheats when you're just sitting there idle, and what you can do to prevent it.

Temperature Sensor in the Electrical Sensor Malfunctions

If your car overheats when you're idling, there's a good chance that the temperature sensor in the electrical sensor is malfunctioning. The sensor measures the temperature of the engine and sends a signal to the computer. If the sensor isn't working properly, it won't be able to detect when the engine is getting too hot and will continue to heat up the car.

There are a few things you can do to check if the sensor is causing your car to overheat: first, check that the temperature gauge is accurately reading the actual temperature of the engine. If it's not, then the sensor may be faulty. Second, if you have access to a volt meter, test whether or not the voltage coming from the electrical sensor is consistent with what should be coming from it. A malfunctioning sensor will cause fluctuations in voltage.

If neither of these tests reveals a problem with your electrical sensor, then you may need to replace it. If all else fails and your car continues to overheat when you're idling, there's a good chance that your radiator is failing and needs to be replaced.

The Radiator Fan Has a Problem

If your car overheats when you're sitting idle, it may be because your radiator fan is not working. The radiator fan is responsible for moving air from the engine bay to the hot exhaust system. If the fan isn't working, the engine will overheat and the car will start to smoke.

The most common reason a radiator fan might not be working is because of a broken belt or motor. If you can't hear or feel the fan when you press down on it, it may be damaged and needs to be replaced. To check if your radiator fan is working, first, check to see if the engine temperature is high enough. If it isn't, then your fan may not be the issue. If your car overheats when you idle, chances are there's a problem with your radiator fan and it needs to be fixed.

Low or No Coolant

Idling your car can cause it to overheat. If your car doesn't have enough coolant, the engine will overheat and it may start to make weird noises. The easiest way to check whether or not your car has low coolant is to take a temperature reading with a thermometer while your car is idling. If the temperature is over 100 degrees Fahrenheit, your car probably needs more coolant.

A Bad Thermostat Valve

If your car is overheating when you're driving, it might be because of a bad thermostat valve. A bad thermostat valve can cause your car to overheat when you're just sitting in traffic or waiting for someone. Usually, the car will overheat if the thermostat isn't opening and closing properly. This can lead to an uncontrolled release of heat from your engine, which can quickly damage it. If you think your car might have a bad thermostat valve, here are some things to check:

  • Look for any unusual noises from the engine, like grinding or knocking. These could be signs that the thermostat is not opening and closing properly.
  • Check the coolant level. If the coolant level is low, the system could be trying to protect the engine by shutting it down prematurely.
  • Check for any leaks around the fan or radiator. Leaks can cause coolant to pool and create an environment that's too hot for the engine.

Clogged Radiator

Your car overheats when you idle because the engine is not getting the same amount of air it needs to function properly. When the car is idling, the fan does not move enough air to cool down the engine. The hot air from the engine combines with the cold air in the air conditioning system and creates a heat wave in your car.


When your car is idling, the heat that's built up from the engine and the air conditioning can cause it to overheat. This can happen because your car isn't getting enough oxygen, which can lead to overheating. An engine that is running too hot is never good, and it could cause a lot of damage that is very expensive to repair.

If you need parts to correct these issues, you can buy them online from our website, or if you are in Florida why not visit our store. PartsMax is the largest Aftermarket Auto Parts warehouse in Florida.