Why Does a Car Shake?
3 Answers
Car shaking can be caused by: 1. Throttle malfunctions, such as throttle blockage or carbon buildup; 2. Excessive impurities in the intake tract, preventing the engine control unit from accurately regulating idle air intake; 3. Spark plug issues, like electrode erosion or damage; 4. Use of low-quality gasoline leading to fuel pump blockage or incomplete combustion of the air-fuel mixture in the cylinders; 5. Fuel injector problems, such as carbon buildup or clogging. Solutions for car shaking include: 1. Cleaning the fuel injectors and refueling at reputable gas stations; 2. Cleaning the intake tract; 3. Cleaning the throttle.
My car had the same issue before, especially when idling at a red light—it shook like a massage chair. After inspection, it turned out to be caused by carbon buildup in the engine. Excessive carbon deposits are like the engine inhaling dust, leading to incomplete combustion and inevitable shaking. Additionally, the ignition system is crucial. If one of the four spark plugs isn’t working, it’s like sitting on a three-legged chair—unstable. A leaking ignition coil can also cause inconsistent firing. Worn engine mounts make the suspension unstable, transmitting vibrations directly into the cabin, which is very noticeable. Poor fuel quality or clogged fuel injectors can also lead to unstable fuel supply, so it’s recommended to use fuel additives regularly to clean the fuel system. Avoid frequent short trips at low speeds; occasionally driving at highway speeds allows the engine to operate fully, effectively reducing carbon buildup.
My car once started shaking when driving at 80 km/h on the highway, and I couldn't even hold the steering wheel steady. The mechanic said it was a tire balancing issue, caused by the small lead weights on the rims falling off, leading to an imbalance in the center of gravity. If the wheel alignment is off, the tires will wear unevenly like walking with a limp, which not only causes uneven tire wear over time but also increases fuel consumption. If the axle is bent or the universal joint is worn, the entire car body will vibrate and shake during acceleration. Uneven brake discs are even more dangerous—when braking, it feels like the car is shuddering, making it prone to losing control during emergency stops at high speeds. These components are all closely related to the chassis and suspension, so it's especially important to check them after driving on rough roads. Worn ball joint bushings can also cause the chassis to become loose and shaky. Chassis issues are directly related to handling and safety, so don't wait until something goes wrong before getting them fixed.
