Idle Air Bypass Screw

Idle Air Bypass Screw 16v:

The Idle Air Bypass Screw is located in the throttle valve housing. Adjusting the screw changes the amount of air which is allowed to bypass the throttle plate, which in turn changes idle speed. But unlike many other Volkswagen models, the 2.0L 16 valve engine with CIS-E Motronic fuel injection (engine code 9A) the Idle Air Bypass Screw on the throttle valve is not used to adjust idle speed. The screw should always be turned all the way in to its stop.