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Q: My car is overheating. I have to run the heater to keep the temperature gauge on the half mark.

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My car overheats when its running. If my car is idling it doesn't overheat. To keep the car cooled down I have to run my heater all the way all the time. I've never seen steam or heard noises coming from the engine. I also don't have any air conditioning when I run the a.c.

My car has 185765 miles.
My car has an automatic transmission.

Hi - there are a couple of possibilities for your overheating situation. The thermostat may not be opening properly, preventing hot water from circulating to and cooling in the radiator. The water pump may be failing and can’t circulate enough hot water through the radiator. If the head gasket on the engine has failed, combustion gases from one or more cylinders "superheat" engine coolant very quickly.

If the coolant level is low, and there are air pockets in the engine, the coolant is literally "boiled away" inside the engine, creating far higher temperatures than a "full of coolant" engine. I would recommend having your car inspected by a mobile, professional mechanic, such as one from YourMechanic, to determine why the car is overheating.

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