Does stepping on the accelerator in P gear have any impact?
3 Answers
Stepping on the accelerator in P gear has no impact on the vehicle. The P gear in an automatic transmission vehicle is the parking gear. In this gear, pressing the accelerator does not transfer power to the transmission system, meaning no substantial damage is involved. It is similar to stepping on the accelerator in neutral, where the engine operates in an idle state. When the vehicle is parked in P gear, the mechanical lock gear teeth secure the transmission output, effectively disengaging the engine from the transmission. There is no power transfer, and revving the engine only increases its RPM without transmitting power to the transmission. Like neutral (N gear), the engine spins freely, and the vehicle does not move. P gear is a special neutral position that mechanically locks the transmission output shaft to immobilize the vehicle. Its primary function is to act as a parking brake, preventing the vehicle from moving. For practical safety reasons, car manufacturers place the P gear in the first position on the gear selector and configure internal mechanisms to ensure the ignition key can only be removed when the gear lever is in P gear. Therefore, P gear is specifically designed for long-term parking in automatic transmission vehicles. Occasionally stepping on the accelerator in P gear will not harm the vehicle, but prolonged operation can cause the engine temperature to rise rapidly. Without cool air intake, the radiator's cooling efficiency significantly decreases, potentially leading to severe issues such as burning the piston's bearings (big and small ends). Additionally, it can negatively affect belts and gears.
Anyone who has driven hundreds of thousands of kilometers knows that occasionally stepping on the gas while in P (Park) mode in a parking lot is quite common, but it's actually bad for the car. P mode is the parking gear, where the transmission is locked. Stepping on the gas only makes the engine rev high with no movement, creating a loud roaring sound. Doing this frequently can cause the engine to overheat, wear out bearings, and potentially damage the transmission's locking mechanism. I remember once at a highway rest stop, a friend was in a hurry and revved the engine hard in P mode to warm it up, causing severe engine vibration. The next day, the dashboard warning light came on. At the repair shop, the mechanic said the electronic system might have falsely triggered a fault code. It's best to develop the habit of turning off the engine immediately after parking and avoid revving in P mode to save on costly repairs later.
As someone who loves tinkering with car mechanics, it's technically not recommended to press the accelerator while in P (Park) gear. When in P gear, the transmission gears are locked and cannot transfer power, so pressing the accelerator only causes the engine to run at high speeds with low load. This not only wastes fuel but may also accelerate wear on engine components such as pistons and crankshafts. Engines are designed to drive the wheels, and prolonged idling can lead to insufficient heat dissipation, especially when parked with the AC on during summer, which can cause issues. For routine maintenance, I suggest checking the ignition system and fuel efficiency to avoid such mistakes. Most automatic transmission vehicles limit the engine RPM to a safe range when the accelerator is pressed in P gear, but it's still best not to try it.
