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Vacuum Throttle Positioner: Testing

  1. Check all wiring and hose connections in system. Repair or replace as necessary.
  2. Apply vacuum from an external source to vacuum throttle positioner. If positioner does not extend, replace it. If it does, pinch off vacuum hose and observe plunger. If it remains extended for one minute or more, unit is okay.
  3. Apply external vacuum to the manifold supply hose connection on the solenoid valve. Disconnect wiring harness from solenoid and ground one terminal of the solenoid. Connect 12 volt source to the other terminal. Watch throttle positioner.
  4. If plunger does not cycle as voltage is applied, replace solenoid. If it does, replace speed switch.
    Fig 1: Schematic of Vacuum Throttle Positioner System for Chrysler Corp. Vehicles
    G09337132Courtesy of CHRYSLER GROUP, LLC