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Vacuum Sensor

  1. Vacuum sensor is located behind right seat under panel. Disconnect electrical connection from ECU.
  2. Connect ohmmeter across terminals No. 7 and 24. Note resistance reading. Internal resistance should be 50-60 ohms. Replace vacuum sensor if resistance is not within specification.
  3. Check vacuum line and vacuum sensor for vacuum leaks. Disconnect vacuum line from pick-up. Install vacuum pump. Using vacuum pump, apply 16 in. Hg and note vacuum drop. Vacuum drop should not exceed 4 in. Hg in one minute.
  4. If vacuum drop exceeds specification, disconnect vacuum hose from vacuum sensor. Plug vacuum line. Reapply vacuum to line. If vacuum drops, inspect for damaged vacuum line. If vacuum did not drop, replace vacuum sensor.
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