Why does Volkswagen LaVida clean the throttle and the car is boring?

Usually, the 4S shop recommends cleaning the automobile throttle every 20,000 km to 40,000 km, but the more frequent the cleaning, the better. Excessive cleaning will gradually clean off the special coating of the throttle chamber, and the inner chamber will lose the coating, which is more likely to cause greasy adhesion. "According to the situation of the car can be appropriately extended.