Does Idling with AC On Damage the Car?
2 Answers
Idling with the AC on does not damage the car. Keeping the car idling with the AC running is a normal operating condition during regular vehicle use. Automobiles are designed and manufactured to account for various operating conditions, so it will not cause any significant harm to the car—only normal wear and tear. However, when idling with the AC on, the engine operates solely at idle speed, which can lead to incomplete combustion of gasoline. Unburned gasoline produces toxic substances such as carbon monoxide. Additionally, passengers inside the car exhale large amounts of carbon dioxide. In hot summer weather, oxygen consumption inside the vehicle is higher than in other seasons. As the oxygen level in the enclosed car gradually decreases, prolonged exposure can cause dizziness, nausea, and weakness—clear symptoms of carbon monoxide poisoning. Therefore, never rest or sleep in an enclosed car with the AC on for extended periods during summer.
I used to always keep the air conditioning on during long-distance drives when taking breaks, until I consulted a professional mechanic. He told me that idling with the AC on does increase the engine load, especially when the compressor continuously draws electricity and fuel. The compressor is connected to the engine, and at low RPMs, the engine simply can't handle it. Over time, carbon deposits build up in the cylinders, and the fuel injectors are prone to gumming up. Moreover, the AC's cooling mainly relies on the condenser's heat dissipation. When the car is stationary, the cooling efficiency drops, making the entire system work as if trapped in a steamer, increasing the risk of malfunctions. So now, if I have to wait for more than 15 minutes, I turn off the AC and open the windows for ventilation—saving fuel and protecting the car.
