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Pulse-Air System

  1. Run engine at idle and disconnect hose between air cleaner and air shut-off valve. A suction sound must be heard at air shut-off side. If not, check for vacuum at blue hose to air shut-off valve.
  2. If no vacuum, clean out vacuum port on throttle housing. If vacuum is present, remove air shut-off valve. If suction is now heard, replace air shut-off valve. If not, replace aspirator valve.