What Causes the Car Body to Shake?
2 Answers
There are 5 main reasons for car body shaking: 1. Severe engine carbon deposits causing body vibration; When the throttle is dirty or the engine fuel injector has severe carbon buildup, gasoline adsorbed on the deposits gets sucked into the combustion chamber after starting, making the air-fuel mixture alternately rich and lean, resulting in idle vibration after startup. 2. Ignition system malfunction: If there are issues with spark plugs, high-voltage wires, or ignition coils, starting the car will also cause body shaking. 3. Brake disc failure: Deep scratches or grooves on the brake disc. 4. Unstable oil pressure: If the fuel pump's supply pressure is abnormal or the intake pressure sensor has incorrect readings or poor performance, it can also lead to body shaking. 5. Aging engine components: Problems with engine parts can transmit vibrations to the steering wheel and cabin, causing shaking during idle.
When I experience body vibrations in my own car, which are usually more noticeable within a specific speed range—such as increased shaking between 60 to 100 km/h—it is often caused by tire imbalance. This means the weight distribution of the tires is uneven, requiring dynamic balancing adjustment. Other possible causes include suspension system failures, such as leaking shock absorbers or fatigued springs, which lose their damping ability and lead to bumps; warped brake rotors that become particularly evident when braking; or even engine misfires or ignition system issues causing tremors at idle. Based on experience, I recommend starting with the tires: check if the tire pressure is appropriate and look for bulges or abnormal wear. If the issue persists after inspection, visit a professional repair shop immediately for diagnosis. Don’t overlook minor problems, as suspension damage can compromise handling safety. Regular vehicle inspections can prevent most vibration issues, ensuring a smooth drive.
