Does Idling in Place Harm the Car?
2 Answers
Idling in place can have certain effects on a car. Prolonged idling can lead to increased fuel consumption, and since the engine does not burn fuel completely during idling, it can produce more carbon deposits, thereby accelerating engine aging. When the engine is idling, there is a significant amount of residual exhaust gas in the cylinders. To ensure stable combustion, the car will automatically enrich the air-fuel mixture. During idling, the oil pressure in the engine is relatively low, which worsens the lubrication condition of moving parts. Unburned fuel washes the cylinder walls, the intake vortex is weak, and fuel combustion is incomplete, making it easy to form carbon deposits. When carbon deposits accumulate to a certain extent, the car's power performance will decline, and over time, it can easily cause engine wear.
I think idling in place depends on the duration. Having driven for decades, short idling like waiting at traffic lights or temporary parking for a few minutes really isn't an issue. But prolonged idling, especially over half an hour, is indeed not car-friendly. The engine running at low speed for long leads to incomplete fuel combustion, causing carbon buildup—particularly in the intake tract and throttle body, which are prone to clogging. Over time, fuel consumption also sneaks up since the engine burns fuel without doing much useful work. The worst part is the strong exhaust fumes, especially in winter when parked underground—the smell can give you a headache. If I have to wait, I turn off the engine and step outside; fresh air beats sitting in the car wasting fuel any day.
