Does idling with the air conditioning on for an hour damage the car?
3 Answers
Idling with the air conditioning on for an hour does not damage the car, but the biggest impact is definitely fuel consumption. Carbon monoxide accumulation can easily lead to poisoning: When the car is stationary with the air conditioning on and the windows and doors are closed, the air inside the car cannot circulate. If carbon monoxide from the engine leaks into the car, it will gradually accumulate, increasing its concentration, which can lead to poisoning or even suffocation. Therefore, try not to turn on the air conditioning in poorly ventilated areas to avoid carbon monoxide buildup and oxygen deprivation. Carbon deposits formation: If the engine speed is too low, it may struggle to power the air conditioning, and even if it does, the engine may run unevenly, leading to incomplete combustion and the formation of carbon deposits. Additionally, idling with the air conditioning on can cause poor heat dissipation in the system, easily leading to overheating of the engine coolant. Overheating can severely damage the engine.
I used to be a carefree driver too, often idling on the roadside with the AC on for an hour or two just to stay cool. Later, my car gradually developed problems. At idle, the engine runs at low RPM, leading to incomplete fuel combustion. Over time, carbon buildup increased, spark plugs got dirty easily, and even starting became difficult. Fuel consumption also skyrocketed—I calculated it burns half a liter per hour, wasting money for nothing. More critically, the catalytic converter can get clogged, making repairs a hassle. Now I’ve learned my lesson: I turn off the AC when parked and step out to stretch, or keep a USB fan for emergencies. A car is like an old friend—don’t mistreat it. Using your brain to save fuel is also more eco-friendly.
As a car owner from the post-90s generation, I'm quite concerned about this topic, since we young people value efficiency and environmental protection. Idling with the AC on for an hour is indeed not ideal—it forces the engine to operate inefficiently, increases carbon buildup, and can shorten component lifespan in the long run. Plus, the fuel consumption is shocking, burning at least 0.5-1 liters per hour. With soaring gas prices, it's a real wallet-drainer. I usually monitor emissions via a car app, which shows idling significantly increases CO2 output. My advice: in summer, roll down the windows for ventilation when parked, or install a solar-powered fan—it saves money and reduces your carbon footprint.
