What Causes Shaking When Starting an Automatic Transmission Car?
4 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.
I've driven quite a few automatic transmission cars, and I always find the shaking during startup particularly annoying, feeling the car body tremble. The most common cause is a faulty engine mounting system, where the brackets are loose or the rubber pads have cracked and can no longer absorb vibrations. There could also be issues on the transmission side, such as insufficient torque converter oil pressure or a slipping lock-up clutch, especially common in older vehicles. The ignition system, like spark plugs that have accumulated carbon deposits over time, can affect ignition, causing uneven power delivery during startup and resulting in shaking. It's important to develop the habit of gently accelerating when starting off, avoiding sudden bursts. If the shaking is severe, it's best to visit a 4S shop as soon as possible to check the oil pressure and mounting brackets, and also to see if the idle is stable. Regular maintenance, such as changing the oil and inspecting the mounting brackets, can greatly prevent this issue from occurring. Otherwise, if left unchecked, the repair costs can become significantly higher.
When experiencing startup shaking, I usually first check the engine mounts to see if the rubber parts are cracked or displaced. Next, inspect the transmission fluid level - if it's black and smells bad, the oil needs changing; torque converter failure is also common. Dirty spark plugs or faulty ignition coils in the ignition system can cause unstable combustion leading to shaking. Simple self-check: after warming up, gently press the accelerator to observe RPM - if it surges unstably, it might be a mount issue. Don't panic, most of these problems are repairable. Recommend having technicians inspect mounts and transmission fluid during every 10,000km maintenance for early detection. Ignoring this may worsen engine vibration and shorten its lifespan.
