[Porsche944]

Either the throttle plate mechanical stop or the Throttle Position Switch are out of adjustment.

Remove the throttle body. Loosen the Throttle Position Switch. Loosen the jam nut on the mechanical stop screw. Back the stop screw out until it does not touch the mechanical stop arm. Verify that the throttle plate is fully closed. (Hint: This is a real good time to clean the throttle body!)

With the throttle plate fully closed, turn the mechanical stop screw in until it just touches the stop arm. Turn the mechanical stop in an additional 1/2 turn and tighten the lock nut.

Now you can set the TPS so the micro switch makes a soft 'click' just as the throttle plate comes off the seat.

Reinstall the throttle body and you're done.