Should the car be in P or N gear when warming up?
3 Answers
When warming up the car, it should be in P gear. Below is a related introduction to the P and N gears in a car:1. P gear: P gear is a special neutral gear that mechanically locks part of the transmission output shaft to secure the vehicle. Its function is to act as a brake after parking, preventing the vehicle from moving. For practical safety reasons, car manufacturers place the P gear in the first position of the gear shift console and set an internal mechanism that forces the car key to be removable only when the gear shift lever is moved to the P gear position. Therefore, P gear is specifically designed for long-term parking in automatic transmission cars.2. N gear: N gear, also known as neutral gear, is used to disconnect the power transmission between the engine and the transmission.
Every time I start my car to warm it up, I always make sure to put it in P (Park) mode instead of N (Neutral). The reason is simple: P mode is the parking gear that directly locks the transmission, keeping the wheels stationary. Even on a slope, the car won't slide or roll, preventing potential hazards. Warming up the car in N mode is different—the wheels can rotate freely, and if the parking brake isn't fully engaged or the ground is uneven, the car might quietly roll away, especially on rainy or snowy days, which can be dangerous. I've been driving automatic transmission cars for over a decade, and this habit gives me peace of mind. Although modern car models don’t require prolonged warm-up, idling in P mode for 30 seconds to a minute allows the engine to warm up smoothly, followed by low-speed driving for more efficient heating. For manual transmission cars, shifting to neutral while warming up is acceptable, but it's still essential to engage the handbrake as a precaution. In short, safety comes first—choosing P mode is simple, reliable, and helps extend the vehicle's lifespan.
As a car enthusiast, I know that using the P (Park) gear is safer than N (Neutral) when warming up the engine. The P gear locks the wheels with a mechanical system, preventing the vehicle from moving during warm-up, while the N gear lacks this locking feature, allowing slight wheel slippage at idle, which increases risks—especially on uneven terrain or if the brakes fail. Most automatic cars require the P gear to start the engine, as some models restrict or even trigger warnings when started in N. Avoid prolonged warm-up—just 30 seconds is enough, followed by low-RPM driving for faster engine heating. For manual transmissions, neutral is fine, but ensure the handbrake is firmly engaged. My experience confirms that using P gear protects the drivetrain, reduces wear, and aligns with modern energy-efficient driving practices. Adopting this habit has significantly improved my driving reliability.
