Does leaving the car in P gear without turning off the engine for a long time damage the vehicle?
2 Answers
Leaving the car in P gear without turning off the engine for a long time can damage the vehicle. The P gear locks the transmission gears, which can cause impact on the transmission. The effects of leaving the car in P gear without turning off the engine for a long time include: 1. The intake vortex weakens, leading to poor fuel atomization and incomplete fuel combustion; 2. Increased fuel consumption by the engine; 3. Deterioration of lubrication conditions. The gears on an automatic transmission car are divided into: P for Park, R for Reverse, N for Neutral, D for Drive, L for Low, and S for Sport mode. When the vehicle needs to be parked for a long time, especially on a slope, it should be shifted to P gear, at which point the wheels are mechanically locked, ensuring the vehicle cannot move while stationary.
The other day at the repair shop, I was chatting with the mechanic about the issue of leaving the car in P gear without turning off the engine. The mechanic said the transmission isn't really a concern—P gear is specifically designed for parking, and the locking mechanism can hold the car steady. But keeping the engine running at low RPM isn't ideal; burning fuel like that isn't exactly economical. Over time, carbon buildup becomes a problem, especially with direct-injection engines—if the fuel injectors get clogged, repairs can cost hundreds. In summer, it's even more critical. Running the AC compressor continuously while idling can lead to overheating. The most extreme case I've seen was someone idling for three hours and draining the battery, eventually needing a rescue vehicle. If you're waiting for more than twenty minutes, it's much better to turn off the engine, get out, and stretch your legs.
