What are the hazards of turning off the engine without shifting to P gear?
2 Answers
The hazard of turning off the engine without shifting to P gear is that it affects the lifespan of the transmission and engine. It is recommended to shift to P gear before parking and turning off the engine. P gear mechanically locks the output shaft of the transmission to secure the car, preventing it from moving. The main purposes of P gear: 1. Parking on flat ground: P gear functions as both neutral and includes a braking mechanism. When temporarily parking on level ground, shifting to P gear puts the car's transmission in neutral operation, completely interrupting power transmission from the engine to the output shaft, allowing the driver to leave the engine running during short waits. 2. Parking on slopes: The core function of P gear is to enable safe and lasting parking on slopes for automatic transmission cars. If parking on a slope, the handbrake bears a significant braking load, and springs and wires related to braking may deform over time, potentially leading to loss of braking force and vehicle rollaway. To prevent difficulty in disengaging due to excessive pawl engagement, always use the handbrake before shifting to P gear when parking on a slope, regardless of the duration. 3. Forced braking: In automatic transmission cars, the key can only be removed when the gear is in P gear, effectively forcing the driver to ensure the vehicle is secured before leaving with the key. 4. Neutral ignition: In automatic transmission models, the engine can only be started in P gear or N gear, preventing sudden vehicle movement and potential accidents.
Every time I see this issue, I feel a bit nervous because shutting off the engine without shifting to Park (P) can be quite harmful. The main concern lies with the transmission: the P gear locks the transmission gears. Forgetting to engage it leaves the transmission unlocked, and after shutdown, the internal gears may experience uneven force, leading to jamming or wear. Over time, this can significantly shorten the transmission's lifespan, with repair costs being alarmingly high. Safety-wise, if parked on a slope or uneven ground, the car may roll away, posing an accident risk—there have been real cases where cars slid and crashed into walls after the driver exited. Electronic systems are also affected, such as abnormal battery drain or fault codes appearing during the next startup, causing difficulty in ignition. My advice is to develop the habit of shifting to P before shutting off the engine—it saves both peace of mind and money.
