Why does the car shake like a convulsion when accelerating?
2 Answers
The following are the reasons for body shaking during acceleration: 1. Engine mount pad: Aging of the engine mount pad. 2. Chassis: Loose chassis. 3. High engine temperature: When the engine temperature is too high, the ECU controls the fuel injection system to inject more fuel, making the air-fuel mixture richer. At this time, sudden acceleration will cause the engine to shake. 4. Poor tire grip: Shaking may also occur during sudden acceleration. Below are extended reasons why the car cannot accelerate beyond 60 km/h: 1. Insufficient engine speed: The gear is too high, causing drag and lack of power. It is recommended to shift gears above 2500 RPM. 2. Just going uphill: The car may be going uphill or carrying too much weight, making it difficult for the engine to accelerate. 3. Low-speed engine: The engine is a low-speed type, with insufficient torque and horsepower at high RPM. 4. Untimely gear shifting: For example, using only 3rd gear to reach 60 km/h makes it difficult to accelerate further. This can also be caused by fuel supply system failures, failure to control fuel pressure or ignition timing as required, or issues with spark plugs and high-voltage wires.
As a seasoned driver with over 20 years of experience, I've also encountered situations where the car shakes violently like convulsions during acceleration, feeling as if the body is trembling. The main cause is usually an issue with the ignition system, such as aging spark plugs or damaged ignition coils, leading to uneven ignition in the cylinders and insufficient fuel supply. Fuel system problems are also common, like clogged fuel lines or unstable fuel pump pressure, making the engine struggle. A dirty air filter affecting air intake can worsen the shaking, and unbalanced or severely worn tires can amplify vibrations at high speeds. Once, my car shook badly during acceleration on the highway, and upon inspection, the spark plugs were heavily carbonized—replacing them fixed the issue. I recommend starting with simple checks: see if the spark plugs are blackened or have large gaps, and whether the air filter is dirty and needs replacing. Basic maintenance like this can prevent major issues. Ignoring it not only damages the engine but could also lead to accidents. Regular maintenance is key—checking the fuel system and ignition components every 5,000 kilometers can save a lot of hassle.
