What Causes Body Shaking During Acceleration?
2 Answers
Body shaking during acceleration can be caused by the following reasons: Severe Engine Carbon Buildup: The most common cause of car shaking is a dirty throttle body or excessive carbon deposits in the fuel injectors. When there is too much carbon buildup inside the engine, the gasoline sprayed by the cold-start injector is largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture during cold starts. This makes starting difficult. In such cases, the car will only start easily once the carbon deposits have absorbed enough gasoline to become saturated. After starting, the gasoline adsorbed on the carbon deposits is sucked into the combustion chamber by the engine's vacuum, making the air-fuel mixture too rich. This fluctuation between lean and rich mixtures causes idle shaking after a cold start. The lower the temperature, the more fuel is required for a cold start, and the presence of carbon deposits significantly affects whether the cold start proceeds smoothly. Ignition System Issues: Check the condition of the spark plugs, high-voltage wires, and ignition coils. Poor performance in the ignition system or weak sparking from the spark plugs can also lead to such symptoms. Unstable Fuel Pressure: If you have already cleaned the engine carbon deposits, throttle body, replaced gaskets and spark plugs, but still experience body shaking at idle, it is recommended to visit a 4S shop to check the fuel supply pressure and the intake pressure sensor. Abnormal fuel pump pressure or incorrect readings and poor performance of the intake pressure sensor can both cause body shaking. Aging Engine Components: Car shaking can also be related to aging engine mounts (also known as engine mounts). Engine mounts act as the engine's shock absorption system, absorbing minor vibrations during operation. If the engine mounts are faulty, these vibrations will be transmitted to the steering wheel and the cabin, causing shaking at idle.
I've noticed that body shaking during acceleration is quite common, mainly related to the engine. Spark plugs with worn electrodes from years of use can cause ignition issues leading to engine vibration; aging engine mount bushings fail to absorb vibrations, transmitting them to the body; improper wheel balancing makes tires wobble during acceleration, especially noticeable at high speeds; fuel system problems like insufficient fuel pump pressure or clogged air filters can cause unstable combustion and shaking; worn drive shaft universal joints creating imbalance is another major factor. As someone with over a decade of driving experience, I recommend starting with replacing spark plugs and checking tire pressure. Don't underestimate these small issues - long-term neglect can accelerate engine wear and compromise driving safety. Timely maintenance ensures smoother and safer vehicle operation.
