Excelle 13 1.5 shakes at idle manually. When waiting for the red light, it shakes intermittently. Putting your hand on the steering wheel is very sensible, invisible to the naked eye, only.

1. The most common cause of serious engine carbon deposition leading to vehicle jitter is that the throttle valve is too dirty or the fuel injector has too much carbon deposition. 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. In addition, the lower the temperature, the more oil is needed for cold start, and the existence of carbon deposit will affect the smooth start. The solution is to clean the oil circuit and check whether there is carbon deposit in the idle motor, which should be cleaned. 2. Ignition system problems Check the working conditions of spark plugs, high-voltage lines and ignition coils. Poor ignition system and poor spark plug misfire can also lead to such failures. The solution is to check whether there is too much carbon in the spark plug and replace the spark plug. 3. The oil pressure is unstable. If the engine carbon deposit has been cleaned, the throttle valve has been cleaned, the oil pad and spark plug have been replaced, and the body is still shaking at idle speed. I suggest you go to the 4S shop 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, the car body will shake. The solution is to check the oil pressure and replace the parts if necessary. 4. The aging of engine parts and automobile jitter are also related to the aging of engine feet. The engine foot is actually the damping system of the engine. 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.