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Q: My air conditioner blows warm when idle, looses coolant and starts to overheat.

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My explorer started blowing warm air when idling. A week later, it was blowing warm air at high speeds and the engine got all the way hot. So I checked it out and the coolant and the oil was low. I filled up the coolant and added oil, and the next day had an oil change and the ac worked fine for a week. Well it started back. It hasn't got hot on me yet and the oil is fine but ac blowing warm while idling and i'm loosing coolant. When I got out of it today after driving awhile, the coolant was bubbling out from the overflow cap. What is causing this? The fan has resistance when trying to spin it and it seems to stay on from the time you cold start the vehicle. But if the fan clutch was stuck engaged then it wouldn't be overheating, right?

My car has 165000 miles.
My car has an automatic transmission.

A: Hi! I have a couple of thoughts that may he...

Hi! I have a couple of thoughts that may help you sort out the issues with your Explorer. There may be separate root causes of the issues with the air conditioning system and the cooling system.

The first thing I would do is a pressure test on the cooling system. This will help to identify whether there are any leaks in the cooling system.

Something as simple as a faulty radiator cap can allow coolant to bubble over out of the radiator. I would just put a new radiator cap on it.

Your engine may actually have a blown head gasket. One of the symptoms can be engine compression leaking into the cooling system and over-pressurizing it to the point of pushing coolant past the radiator cap and out of the overflow. There is a testing tool that can can be helpful called a block tester. It is used to identify the presence of combustion gasses in the cooling system.

A qualified technician from YourMechanic can come to your home or office to inspect your AC system and recommend the best path to repair.

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