What are the reasons for an automatic transmission car not moving when in D gear?
3 Answers
Automatic transmission cars not moving when in D gear can be caused by various situations: 1. The driveshaft rotates but the car cannot move; when lifting the rear axle and turning one rear wheel, the driveshaft does not rotate, and the rear wheel reverses; 2. After the car starts, the transmission is in a certain gear but the driveshaft does not rotate, possibly due to a broken shift fork or loose fixing screws. Precautions for shifting gears in automatic transmission cars: 1. Do not press the accelerator pedal when shifting gears; 2. Do not immediately press the accelerator pedal hard after shifting into gear; 3. The vehicle can only be started in P or N gear; 4. The brake must be pressed to move the gear lever out of P gear; 5. Do not shift into N gear while driving to coast; 6. Do not push into P gear while the car is moving; 7. When changing driving directions, switching between D and R gears should only be done after the vehicle has come to a complete stop; 8. Placing the gear in N while driving prevents the oil pump from supplying oil normally for lubrication, which can raise the temperature of internal transmission components and cause damage.
As an experienced automatic transmission driver, I once encountered a situation where the car wouldn't move despite being in D gear, which gave me quite a scare. Looking back, it was due to insufficient transmission fluid causing low oil pressure, which prevented effective power transfer. Similar situations could also be caused by excessive wear of clutch plates or torque converter failure, where internal components age and deform; or issues with the electronic control system, such as sensors falsely reporting the gear position, making the computer think it's still in neutral. This problem is quite frustrating. When dealing with it, the first step is to pull over, stop the engine, and avoid forcing the car to move to prevent engine damage. After that, check the fluid level and try adding high-quality transmission fluid. If that doesn't work, the only option is to tow it to a professional repair shop. Regular vehicle maintenance is key—checking fluid conditions with each season change can significantly reduce this risk. Older cars are especially prone to such issues, so don't skimp or delay maintenance.
Having fixed many automatic transmission issues, I've seen numerous causes for D-gear idling. The most common is fluid problems—old oil deteriorating into thick clumps affecting pressure transfer, or low oil levels failing to pump up; next is clutch pack damage like cracked pressure plates failing to engage, causing power loss; electronic control issues such as faulty gear switches or ECU malfunctions often disrupt signals. Inspection steps: Pop the hood to check dipstick levels, try an oil change; if no improvement, professional clutch diagnosis is needed. Once, a user ignored this, leading to a full transmission replacement costing thousands. The lesson: address it early, don't delay—safety first, don't gamble with your car.
