What is the idling jitter after running through the high speed?

Idle jitter after high-speed driving is caused by dirty throttle, air leakage in vacuum tube and excessive carbon deposition in injector. 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 a large amount of carbon deposit during cold start, which makes it difficult for the lean mixture to start cold. In this case, it is easy to start the car only if the gasoline with carbon deposits is saturated. After the car is started, the gasoline adsorbed on the carbon deposit will be sucked into the cylinder by the vacuum suction of the engine for combustion, which will make the mixture rich, and the combustible mixture of the engine will be diluted and enriched, resulting in a cold start. The lower the temperature, the more oil is needed for cold start, and the more carbon deposit will affect the success of cold start. Another reason is inferior oil. Because of driving at high speed for a long time, the oil will become thinner and thinner, which will not play a role in lubrication and lead to engine jitter. Changing a barrel of synthetic oil will make you feel like you have changed to a new car.