What Causes Shaking When Starting an Automatic Transmission Car?
2 Answers
Here are the reasons for shaking when starting an automatic transmission car: 1. The throttle body is too dirty, causing uneven air intake and operation; 2. Fuel line blockage, leading to insufficient fuel supply at low throttle and uneven operation of engine cylinders; 3. Abnormal transmission operation; 4. Broken or burned high-voltage wires or spark plug failure causing some cylinders to misfire; 5. Whether the battery voltage is within the specified range. Correct method for starting an automatic transmission car: 1. Turn on the power, then start the car; 2. After ignition, press the brake, shift to D gear, release the handbrake, and gently press the accelerator to start; 3. After starting, accelerate appropriately according to road conditions. Precautions for driving an automatic transmission car: 1. Use one foot to control the car; 2. Use the gear appropriately when waiting at traffic lights.
I've been driving for ten years, and the most common cause of automatic transmission startup shaking is engine mount issues. When the rubber vibration dampening pads on the frame age or crack, vibrations transmit directly to the vehicle body, especially noticeable during cold starts. Another reason could be torque converter failure in the automatic transmission - worn clutch plates inside cause unstable oil pressure, resulting in shaking when accelerating. Sometimes spark plug carbon buildup or faulty ignition coils also cause uneven combustion leading to vibrations. I recommend avoiding aggressive throttle starts and applying gradual acceleration to reduce impact. Regularly inspect engine mounts and transmission fluid levels - replace if too dirty to prevent many issues. Otherwise, prolonged neglect may damage more components like exhaust pipes or axles. Don't underestimate this shaking - it can warn of major problems. Prioritize safety and seek professional repair immediately.
