How many kilometers does the BMW three-series throttle need to be cleaned?

How often does the BMW 3 Series throttle have to be cleaned? Under normal circumstances, the 4S shop recommends cleaning the throttle every 20,000-40,000 kilometers, but the frequency of cleaning the throttle should not be as high as possible. Excessive cleaning will gradually remove the special coating of the throttle chamber, and the inner chamber will lose the coating, which is more likely to cause greasy adhesion. Throttle cleaning procedure: 1. Find the throttle position, which is behind the air inlet and connected to the air cleaner; 2. Remove the empty filter box first, and then remove the hose connecting the throttle valve and the empty air filter element; 3. Then pull out the throttle wire and sensor, and unscrew the fixed throttle bolt to complete the disassembly; 4. Then spray it on the oily carbon deposit with special throttle cleaner, wait for the solvent to dissolve the carbon deposit, and dry it for 1-2 minutes.