How does Audi a5 set idle deceleration?

1. Slowly loosen the throttle opening adjusting screw of Audi a5 with a screwdriver, and screw it in slightly when the engine is about to turn off, so as to keep the Audi a5 engine running.

2. Adjust the adjusting screw of Audi a5 idling mixture to accelerate the engine.

3. Turn out the valve opening adjustment of Audi a5 again to realize slow idle, and turn off the engine after acceleration, thus setting Audi a5 to slow idle.