Does Idling a Car with the AC On Consume Fuel?
2 Answers
Idling a car with the air conditioning on consumes a significant amount of fuel, typically around 2L/h. If the car is low on fuel, it may continue to burn until the engine stalls. Precautions for idling a car with the AC on: When a car is idling, incomplete fuel combustion produces a large amount of carbon monoxide. The longer the idling time, the higher the concentration of carbon monoxide around the vehicle. Prolonged idling can lead to dangerously high levels of carbon monoxide inside the car, which can cause carbon monoxide poisoning or even death if passengers are present, leading to safety hazards. Incomplete fuel combustion during idling can also cause engine carbon buildup. Severe carbon buildup can affect the car's ability to start normally, reduce engine power, increase fuel consumption, and result in excessive exhaust emissions. Extended idling also releases large amounts of exhaust gases, including PM2.5, which pollutes the air and causes significant environmental damage.
I've been repairing cars for over a decade, and this question comes up every single day. As long as the engine is running, the AC compressor will consume engine power. Take my family's SUV for example - idling with AC on for one hour burns roughly over 1 liter of fuel. During idle conditions, fuel doesn't burn completely, leading to carbon buildup in the exhaust pipe, and over time it might even clog the catalytic converter. If you're waiting in the car during summer, I strongly recommend parking in the shade and cracking the windows for ventilation - it's way more fuel-efficient than running the AC.
