Throttle Full Open Switch: Adjustments

Throttle Switch Testing:

NOTE: If the the throttle switches are misadjusted, the engine may surge at idle or cutout during a steady driving speed or light throttle applications.
The throttle valve basic adjustment must be OK. Refer to FUEL SYSTEMS.

IDLE SWITCH

1. Disconnect the throttle switch harness connector.
2. Connect test adaptor VW 1501, or equivalent to the throttle valve switch plug.
3. Connect a suitable volt/ohm meter between terminal 1 and 2 of the test harness.
4. Open the throttle 1/3 and measure the resistance.

^ The correct measurement should be infinite ohms (no continuity).

Adjustment Of Throttle Switches:

5. Insert a 0.006 in. (0.15 mm) feeler gauge between the stop screw and the throttle lever.
6. Close the throttle valve.

^ The measurement should change to 0 ohms (continuity) when throttle is closed against the feeler gauge.

7. If the adjustment is incorrect loosen the idle switch and reposition it as necessary to obtained the correct results.
8. Recheck the switch closing point.

Throttle Switch Testing:

FULL THROTTLE SWITCH

1. With the ignition "OFF" disconnect the throttle switch harness connector.
2. Connect test adaptor VW 1501, or equivalent to the throttle valve switch plug.
3. Connect a suitable volt/ohm meter between terminal 2 and 3 of the test harness.
4. Screw protractor VW 3084, or equivalent to the top of the throttle shaft.
5. Attach the pointer of the protractor to the throttle cable mounting bracket.
6. Open the throttle lever completely to full throttle stop; then zero the pointer for the protractor.
7. Close the throttle approx. 20°.

^ The volt/ohm meter should read infinite ohms (no continuity).

8. Slowly push in the direction of full throttle stop until the full throttle switch closes and the volt/ohm meter reads 0 ohms (continuity)

^ The full throttle switch must close (continuity) at 10° ± 2° before full throttle stop.

If the adjustment is incorrect loosen the full throttle switch and reposition it as necessary to obtained the correct results.

9. Secure the switch hold-down screw and repeat the test procedure.
10. Press the accelerator pedal to the floor.

^ The throttle valve must be open fully.

If the throttle valve is not fully open adjust the accelerator cable. Refer to FUEL SYSTEMS.