Why Does My Car Overheats When Idling With AC On?

If your car is overheating when idling with the air conditioning on, there are a few things to check before you start spending money. The first thing to do is make sure that the air conditioner and heater are working properly. A faulty air conditioner or heater can cause your car to overheat while idling.

Check the coolant level. If it’s low, this could be causing your car to overheat while idling. If none of these issues seem to be causing your problem, then you may want to consider replacing your thermostat or radiator cap. You can also try cleaning out the radiator and adding coolant if needed.

What are the symptoms?

One of the symptoms of a radiator problem is overheating. If you’re driving around with the air conditioner on and notice that your car overheats, it could be caused by a faulty radiator. This can also happen at low speeds in stop-and-go traffic or while idling.

The coolant that circulates through your radiator is used to regulate the temperature of your engine by transferring heat away from it. If there is a leak in your system, or if there are cracks or other damage to the radiator itself, this will prevent coolant from circulating properly and keep it from reaching optimal temperatures. As a result, the engine will overheat and become damaged if left unchecked.

Overheating can also cause problems with other parts of your vehicle, including damage to hoses and belts as well as damage to other components like bearings or seals inside the engine itself. These parts may need replacing if they suffer from heat damage due to overheating caused by radiator issues like these ones described above.

What are the possible causes?

A car that overheats when idling with the AC on is most likely caused by a problem with the thermostat. The thermostat is responsible for controlling the temperature of the engine coolant, ensuring that it stays within a certain range. When your car’s engine is off, the thermostat should be closed and prevent coolant from passing through to the radiator. If your car starts to overheat while idling in traffic, this generally means that there is a problem with either the thermostat or its related parts.

What are some ways you can prevent my car from overheating?

Don’t drive with the AC on for long periods of time. Try to only use the AC when driving short distances or during traffic jams where you’re going to be stopped for a while. If possible, turn off the AC when you’ve reached your destination.

If you have an older car, check your radiator regularly for leaks and cracks. If there are any cracks or leaks, replace them immediately so that they don’t cause further damage to your car’s engine.

Check your coolant level regularly (at least once every two weeks). If it gets too low, then it could cause problems with the engine’s ability to cool itself down properly.

How do you fix a car that is overheating?

When you’re idling with your air conditioning on, your car is working extra hard to cool the air inside. The engine is also working hard to generate enough power to do both of these things at once. This can cause your engine to overheat if it’s not designed to handle this kind of stress.

If you have a modern vehicle and are having problems with overheating when idling with the AC on, make sure that you’re using an approved engine coolant and that it has been flushed regularly. Make sure that there aren’t any leaks in the system.


It’s important to note that overheating is not a problem that can be solved simply by turning off the AC. If you notice your car overheating when idling with the AC on, it’s time to do some troubleshooting. The first thing you should do is check your coolant level and refill it if necessary. If that doesn’t work, check your thermostat and make sure it’s working properly if not, replace it. You might also have a blocked radiator or hoses that need replacing.

Steven Hatman
Steven Hatman

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