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THERMO Vacuum Valve

  1. Remove valve from intake manifold. Connect hoses to ports for air cleaner and EGR valve (2 upper ports) and plug port to canister (lower port). Submerge valve into a container of cold water.
    NOTE: DO NOT allow water to enter valve.
  2. Heat water slowly. Blow air into valve and confirm valve opens or closes in response to water temperature.
  3. Thermo vacuum valve should be completely open below 86°F (30°C) and should completely close above 104°F (40°C). Remove thermovalve from water. Connect hoses to vacuum valve EGR valve port and canister port, and plug port to air cleaner.
  4. Blow air into valve and confirm that valve opens and closes in response to water temperature. Valve should completely open below 86°F (30°C) and should completely close above 104°F (40°C).
Fig 1: Sectional View of EGR Vacuum Valve & Check Valve
G67259Courtesy of SUBARU OF AMERICA, INC.