Throttle Valve Switch, Checking and Adjusting

Checking And Adjusting Throttle Valve Switch

Note: The throttle valve switch indicates the throttle position to the control unit for the following functions:

Throttle valve closed
- Injection quantity for idle
- Switching off the injection quantity during deceleration fuel shut-off
- Ignition point setting in idle (DLS function)

Throttle valve completely open
- Injection quantity for full throttle





- Check continuity of throttle valve switch at connector 1
Switch must display continuity only during idle and full throttle position of throttle valve switch

- Open throttle valve and close slowly. While doing so, check switching point (continuity) of switch with feeler gauge at idle stop of throttle valve lever
Switching point: gap (a) 0.05 - 0.10 mm (0.002 - 0.004 in) before idle stop

- If necessary, adjust gap (a) with eccentric screw 3 (first loosen screw 2)

Note: Proper adjustment is important.

If gap (a) too LARGE
- Engine will surge when throttled slightly

If gap (a) too SMALL
- Cold engine will stall out when given gas
- Warm engine will have NO fuel deceleration shut-off
- Warm engine will have NO DLS function at idle

Note: The limiting screw for basic throttle valve adjustment must not be changed. If the screw is turned by mistake, it will be necessary to carry out a basic adjustment of the throttle valve.