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THERMO Vacuum Valve

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