Why does the engine shake for a while after starting and then return to normal?
2 Answers
The reasons why the engine shakes for a while after starting and then returns to normal are as follows: 1. Excessive carbon deposits inside the engine. 2. Issues with the vehicle's ignition system. 3. Unstable fuel supply to the engine. 4. Abnormal mixing ratio of the engine's air-fuel mixture. 5. Engine shaking caused by uneven operation of the engine cylinders. Below is a brief introduction to the engine: (1) An engine is a machine that converts other forms of energy into mechanical energy. Modern engines are divided into internal combustion engines, external combustion engines, jet engines, and electric motors. (2) The engine is an important component of a vehicle, and the earliest engines were born in the UK. (3) The parameter used to distinguish engines is the engine displacement. The larger the displacement, the stronger the engine's power output and performance.
When I first bought my car, I also encountered this issue. I would drive to work, and as soon as I started the engine, it would shake violently, but it would smooth out after a few dozen seconds. Actually, this is quite normal, especially in cold weather. The engine oil hasn’t warmed up yet, making it as thick as paste with poor fluidity, causing unstable piston movement. Additionally, the fuel injection hasn’t adjusted properly, leading to incomplete combustion and shaking. My car is an older gasoline model, and the shaking is more noticeable during cold starts in winter, but it stabilizes once the engine warms up. Don’t worry too much—it’s mostly because the engine’s ECU control unit is initializing and adapting to the cold conditions. However, if the shaking persists for a long time or is accompanied by strange noises, you should check the spark plugs or carbon buildup issues. Using higher-quality oil during regular maintenance and periodically cleaning the throttle body can help reduce this startup shaking.
