Does leaving the car idling overnight without moving damage the vehicle?
2 Answers
Leaving the car idling overnight without moving can damage the vehicle because when the engine is running without movement, the circulation of engine oil slows down, leading to insufficient lubrication in the transmission, which can easily cause damage to the transmission. Only by warming up the car can the engine oil return to the upper part of the transmission, making warm-up an essential step. Additional information: 1. After prolonged parking, the engine oil in the engine flows back to the lower part, so when restarting the vehicle after a long period of inactivity, the upper part of the engine lacks lubrication as there is no oil present. 2. After a long period of inactivity, it is necessary to warm up the car for about 30 seconds before driving to ensure that all parts of the engine are filled with oil and properly lubricated, and to allow the gasoline to fully vaporize. Warming up the car helps the engine reach its normal operating temperature, and similarly, the gear oil in the transmission, like the engine oil, may have settled to the lower part of the transmission after prolonged inactivity.
As an automotive repair technician, I frequently deal with similar issues. Leaving the car running but not moving all night is indeed harmful to the vehicle. The main reason is that prolonged engine idling leads to incomplete combustion, generating a large amount of carbon deposits. This not only reduces power output but also increases fuel consumption and, in the long run, damages internal engine components such as piston rings and cylinder walls. If carbon buildup occurs rapidly, repairs can be quite expensive, potentially requiring a full system cleaning. Additionally, excessive idling may cause the engine to overheat, especially if there are issues with the cooling fan or water pump, increasing the risk. Regarding the battery, although the alternator charges it, prolonged idling can overuse the battery, shortening its lifespan. More dangerously, in enclosed spaces, carbon monoxide can accumulate, posing a poisoning risk—so this practice is strongly discouraged. If it's an emergency, ensure the car is parked in an open, ventilated area and limit the duration to as short as possible, such as under an hour. Make it a habit to turn off the engine when parked to protect both your car and your wallet.
