The accelerator is broken, and it is very frustrating when you step on the brakes.

The carbon deposition at the air inlet is serious. Throttle is a controllable valve that controls air to enter the engine. After the air enters the intake pipe, it will be mixed with gasoline to form a combustible mixture. The throttle valve is broken, and there is a sense of frustration when stepping on the brakes. It is the serious carbon deposition in the intake pipe, which leads to the successful combustion. It is connected to the air cleaner and to the engine block.