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Q: When idling, car overheats and A/C blows hot air - 2001 Saturn L100

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When I’m not in motion and my car is just idling, like in my driveway, my car overheats and the air conditioner blows only hot air. If I am driving on the highway and accelerating, there is no overheating and the air conditioner works well blowing nice cold air. If I’m sitting at a red light or a stop sign, the temperature gauge starts to slowly rise and the air conditioner blows cold air. What needs to be done so that my car’s air conditioner will function well again?

Hello. The most likely cause of the issue that your are having would be a faulty cooling fan. The cooling fans purpose is to keep the radiator and condenser for the air conditioning cool during the idling function of the vehicle.

If the cooling fan is not working, this will cause the radiator and condenser to get very hot. When the radiator and condenser get hot, this can cause the vehicle to overheat and the air conditioning not to work. When the vehicle is driving at higher speeds, the force of air that is created towards the vehicle will flow through the radiator and condenser and therefore keep them cool. I would recommend having the cooling fan checked to make sure that it is working properly. If not, I would recommend having the cooling fan replaced.

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