What Are the Causes of Car Engine Shaking?

[DiGavin]

There are three main causes of car engine shaking: 1. 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 can be largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture during cold starts. This makes starting difficult and 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. 2. Ignition system issues. Check the condition of the spark plugs, high-voltage wires, and ignition coils. Poor performance of the ignition system or improper spark plug firing can also lead to such symptoms. 3. Unstable fuel pressure. If you have already cleaned the engine carbon deposits, cleaned the throttle body, replaced the gaskets and spark plugs, but still notice shaking at idle, it is recommended to visit a 4S shop to check the fuel supply pressure and the intake pressure sensor. If the fuel pump supply pressure is abnormal or the intake pressure sensor readings are incorrect or malfunctioning, it can cause the car to shake.