Will an Automatic Car Move Without Pressing the Accelerator?

[LeElias]

When the gear of an automatic car is in P (Park) or N (Neutral), the car will not move whether the accelerator is pressed or not. However, when the gear is in any position other than P or N, the car will move when the accelerator is pressed and may also move without pressing the accelerator. It's important to note that automatic cars should not be put in neutral, as coasting in neutral can damage the automatic transmission. Below are some common misconceptions about using an automatic transmission: Keeping the car in D (Drive) for long periods while parked: If the brake pedal is pressed for an extended period, it forcibly stops the car from moving forward, causing the transmission fluid temperature to rise and the fluid to degrade, especially when the engine is idling higher with the air conditioning system running. High-speed driving: This can potentially burn out the transmission, as the transmission output shaft rotates at high speed while the engine idles, leading to insufficient oil supply from the transmission pump and worsening lubrication conditions.

[DiAlexis]

As a veteran driver with twenty years of experience driving automatic transmission cars, I'd like to share some personal insights. Automatic cars can indeed move slowly without pressing the accelerator, thanks to the power output from the engine at idle speed being transmitted to the transmission. This state is called the crawl speed, and it's most noticeable when starting in D gear. In city traffic jams, I often don't need to press the accelerator constantly—the car just inches forward on its own, saving a lot of effort. But this isn't foolproof—if you're stopped on a slope without braking, the car might roll backward, which is extremely dangerous! I remember one time in a parking lot when I forgot to brake, and the car almost hit a wall. So, when beginners are practicing, they must develop the habit of using the brakes. Additionally, as the car ages, unstable idle speed might affect this function, but regular maintenance of the engine and transmission can prevent issues. Crawl speed does make driving easier, especially at low speeds.

[LeHannah]

When I first started driving an automatic, I was also curious about this. Now I understand: the car can move slowly forward or backward without pressing the accelerator. The engine's idle speed provides just enough power, transmitted through the automatic transmission to the wheels, pushing the car to move. My car easily moves a short distance when starting on flat ground. But for beginners, this slight movement can be dangerous—for example, when parking on a slope, releasing the brake can cause the car to roll, leading to accidents. I recommend that beginners practice brake control more, especially in parking scenarios, and not rely too much on the crawling speed. If the car doesn't move, check if the gear is in P or N, or if there's an engine issue. In short, it's a convenient feature, but safety always comes first.

[JohnnyRose]

Simply put, an automatic transmission car can indeed move without pressing the accelerator. This is due to the engine idling, where power is transmitted to the wheels through the torque converter, creating a low-speed creeping motion. In Drive (D) or Reverse (R) gear, the car will slowly crawl forward. In daily driving, this design is quite considerate, such as when creeping forward at traffic lights without repeatedly pressing the accelerator. However, the transmission is crucial—if it's old or dirty, efficiency can drop. From a maintenance perspective, regularly changing the transmission fluid can make the creeping smoother. Remember not to leave it unattended on slopes, as it can easily slip and cause accidents.