What is the reason why Jetta always shuts down?

Jetta always shuts down for the following reasons: 1, idle flameout fault: when idling flameout, the idle speed should be adjusted according to the actual situation; After adjustment, if the fault disappears, it is improper adjustment of idle screw; If the fault does not disappear after adjustment, open the throttle to keep the engine running, and check the carburetor and intake pipe gasket for air leakage with cotton yarn or paper. 2. Failure of excessive idle speed: When the engine idle speed is too high, the car should be parked on the flat ground, and the choke button and the hand acceleration button should be pressed to the bottom for inspection; Press the throttle rocker arm by hand to close the throttle. If the idle speed is normal, it means that the lever spring of carburetor is too soft.