How to check whether the throttle valve needs cleaning?

How to check whether it is necessary to clean the throttle: the throttle is too dirty, which is obviously characterized by unstable acceleration. These faulty car owners can directly feel it themselves. 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, and the combustion is successful. It is called the throat of an automobile engine, which is connected with the air filter and the engine block. Whether the acceleration of a car is flexible or not has a lot to do with the dirt of the throttle. Cleaning the throttle can reduce fuel consumption and make the engine flexible and powerful.