What is the sign of Nissan hacker's throttle cleaning?

There is no water. How often the throttle of Nissan hacker is cleaned depends on many aspects. But every time you clean the throttle, the sign is that you can't get wet and you need to wipe it by hand. Throttle is a controllable valve, which is used to control air to enter the engine. Above is the air filter, and below is the engine block.