Will an automatic transmission car move without pressing the accelerator?
3 Answers
An automatic transmission car will move without pressing the accelerator. Automatic transmission vehicles do not have a clutch pedal. When the gear is shifted into the driving position, the clutch is already in a connected state. At this time, without the resistance of the brakes, the car will slowly move forward. Automatic transmission cars do not require the driver to manually shift gears; the vehicle will automatically select the appropriate gear based on the driving speed and traffic conditions. Here is an introduction to the gears of an automatic transmission car: 1. P gear is the parking gear; 2. R gear is the reverse gear; 3. N gear is the neutral gear; 4. D gear is the drive gear; 5. S gear is the sport mode. The working principle of the accelerator is: pressing the accelerator pedal directly controls the throttle. The throttle opening will increase, allowing more air to enter the engine. At this time, the ECU will command the fuel injection system to inject more fuel, causing the engine speed to rise and the car to accelerate.
Yes, automatic cars do move forward slowly without pressing the accelerator, which I’ve personally experienced while driving. Especially in parking lots or congested areas, after releasing the brake, the car creeps forward automatically at a very low speed but noticeably. This happens because the engine at idle still delivers a bit of power to the wheels, as if it has nothing better to do. When I first drove an automatic, I wasn’t used to it—once on a slope, I forgot to brake, and the car started rolling on its own; luckily, nothing bad happened. This design is actually an advantage of automatic transmissions, making starts smoother, but safety is key—always combine it with brake control, especially in crowded areas. Once you get familiar with this feature, driving becomes much easier.
From a technical perspective, automatic transmission vehicles can creep forward without pressing the accelerator, relying solely on power transmission at idle speed. When the engine operates at low RPM, a small amount of torque is delivered to the wheels through the transmission and power delivery system, which is somewhat similar to the half-clutch state in manual transmission cars. While studying automotive principles, I discovered this feature is called 'creep,' specifically designed to facilitate starting. It's very user-friendly for driving beginners, but if the idle speed isn't properly adjusted or the car isn't well-maintained, it may appear underpowered or increase fuel consumption. Understanding this can help optimize driving habits, such as utilizing idle speed directly for slow vehicle movements to avoid harsh acceleration.
