Sometimes the steering wheel of my car shakes, sometimes it doesn't. What is the reason?

Idle jitter may have the following four reasons:

1. The engine has serious carbon deposition.

The most common cause of automobile jitter is that the throttle valve is too dirty or the fuel injector has too much carbon deposit. When there is too much carbon deposit in the engine, the gasoline sprayed by the fuel injection head will be absorbed by the carbon deposit during the cold start, which leads to the lean mixture during the cold start and makes it difficult to start. In this case, only when the gasoline adsorbed by carbon deposits is saturated, it is easy to run into the car. After running into the car, the gasoline adsorbed on carbon deposits will be sucked into the cylinder by the vacuum suction of the engine for combustion, which will thicken the mixture and dilute the combustible mixture of the engine, resulting in idling jitter after cold start.

2. Ignition system problem

Check the working conditions of spark plugs, high-voltage lines and ignition coils. Poor working conditions of ignition system and spark plug can also lead to such failures.

3. The oil pressure is unstable

If the carbon deposit in the engine has been cleaned, the throttle has been cleaned and the spark plug has been replaced, the idling vibration of the car body is still found. It is recommended to check whether the oil supply pressure and intake pressure sensors are normal. If the oil supply pressure of the oil pump is abnormal or the value of the intake pressure sensor is wrong, it will cause the body to shake.

4. Aging of engine parts

Car jitter is also related to the aging of engine feet. The engine foot is responsible for absorbing slight vibration when the engine is running. If there is something wrong with the engine foot, these vibrations will be transmitted to the steering wheel and cab, causing idling jitter.