What happened when Jetta stopped on the road and the throttle turned off?

The idle speed of Jetta cold car is unstable when it starts. If you don't step on the accelerator right away, it will stall. The accelerator is dirty, just wash it with carburetor cleaner. By the way, just clean the throttle and nozzle.

Also known as extinction. When the reactor is running at a significant reaction rate, if the temperature of the inlet drops to the lower limit of the multi-state zone, the reaction rate will suddenly drop sharply and the reaction will basically stop. This phenomenon is called extinction. The corresponding inlet temperature is called the extinction point. Generally, it refers to a car stalling.