Does idling the engine for half an hour harm the car?
3 Answers
Idling the car for half an hour can cause certain damage to the vehicle. The main harm is that prolonged or frequent idling can lead to carbon buildup inside the engine cylinders and affect the throttle. When carbon deposits accumulate to a certain extent, they can reduce the car's power performance and, over time, easily cause engine wear. Problems that can occur with engine idling: Inefficient vaporization of gasoline: The normal operating temperature of an engine is approximately between 90 to 110 degrees Celsius. Before reaching the operating temperature, the fuel system is too cold to effectively vaporize gasoline completely, making it harder to ignite and start the engine. Gear oil flows to the lower part of the transmission: Regarding the lubrication of transmission gears, this is something most people don't understand and often overlook. Similar to engine oil, gear oil in the transmission flows to the lower part when the car is cold. Difficulty shifting when the car is cold: Only when the car is moving does the operation of the gears bring the gear oil from the bottom to lubricate the upper part. This is why most cars experience difficulty shifting when cold.
Will idling the engine for half an hour damage the car? This question depends on the situation. Short-term idling is generally fine, such as warming up the engine for a few minutes, but prolonged idling like half an hour can pose some risks. From my driving experience, I've noticed that the engine doesn't burn fuel completely when idling, leading to carbon buildup. Over time, residues can accumulate inside the cylinders, affecting performance and fuel efficiency. Additionally, the cooling system might face issues—the fan relies on driving or load to cool down, and idling alone doesn't make the fan spin fast enough, especially in summer when water temperatures can rise, potentially damaging the fan or belt. The battery also keeps discharging, and if it's old, it might not start the engine. Overall, it's not a good practice, and I recommend avoiding prolonged idling. If you need to use the AC or wait at a signal, keeping it under 10 minutes is best. During regular car maintenance, just check these components—safety first.
Keeping the engine idling for half an hour is indeed not ideal. From an automotive design perspective, engines are inherently meant for driving. When running without load, fuel combustion efficiency is low, essentially wasting gasoline—which isn't cost-effective. Based on my years of driving experience, prolonged idling can lead to increased carbon buildup because the fuel injected doesn't burn completely, gradually accumulating on the pistons and injectors, potentially causing engine vibrations or sluggish acceleration. The cooling system also suffers, as the fan doesn't spin fast enough, slowing radiator cooling. In high temperatures or with older vehicles, this might trigger overheating warnings. The battery drains too—though modern cars have charging protection, frequent idling can shorten battery life. From an environmental standpoint, excessive CO2 emissions are harmful. While idling for 30 minutes isn't catastrophic, it's best avoided. Turning off the engine at red lights or in traffic saves fuel and protects your car.
