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Throttle Positioner

  1. With vehicle on a dynamometer, rear wheels raised, or road testing vehicle, raise vehicle speed slowly. Throttle positioner should turn on at about 15 MPH. Raise vehicle speed to above 25 MPH and then let engine decelerate to about 10 MPH. Throttle positioner should turn off.
  2. Disconnect throttle positioner hose from vacuum switching valve. Throttle positioner linkage should turn off (not contacting throttle lever) when hose to throttle positioner diaphragm is sucked. See Fig 1.
    Fig 1: CHECKING THROTTLE POSITIONER
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