Why didn't Toyota Wilanda's maintenance manual say to clean the throttle?

Toyota Willanda needs professional nursing knowledge to clean the throttle, which is not written in the maintenance manual. Check the tightness and aging of belts of generators, air conditioners, water pumps and booster pumps during maintenance of Toyota Willanda. The reason why the maintenance manual does not explicitly require cleaning the throttle is because the throttle can be cleaned and the throttle controls the intake air. The deeper you step on the accelerator pedal, the greater the throttle opening and the larger the air intake, which can meet the combustion demand of more fuel injection.