What are the symptoms of dirty throttle?

Symptoms of dirty throttle are: 1. When a car refuels, it will feel that the throttle is stuck, heavy, and the speed is slow. When idling, the speed of stepping on the throttle rises slowly and the response is slow. When driving, release the throttle and the speed will drop immediately; 2. An obvious problem that affects the accuracy and smoothness of engine air intake is that it may cause jitter or even flameout when idling, and the fuel valve speed is not smooth. The reasons for dirty throttle are: 1, vehicle environment, poor filtration of intake filter element, and heavy dust in the surrounding environment; 2, the variety of engine oil is not good, and the evaporation is large; 3, crankcase oil vapor and impurities; 4. After the flameout, the throttle should not be very tight. Inhale some dust, and many a mickle makes a mickle.