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Vacuum Motor Test

  1. Check all hoses and connections for proper hook-up. With engine off, observe damper door through snorkel opening. The door should be open to outside air.
  2. With an external vacuum unit, apply 7 in. Hg of vacuum to diaphragm assembly through hose disconnected at sensor. Damper door should close when vacuum is applied. If not, check for vacuum leak, or binding linkage.
  3. With vacuum applied, bend hose to trap vacuum in diaphragm assembly. Damper door should remain closed. If not, replace diaphragm assembly.
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