Thermal Vacuum Valve

Remove thermal vacuum valve from intake manifold. Connect hoses to 2 upper ports and cap lower port. Submerge valve in container of water.
CAUTION: Do not allow water to enter valve.
With water below 86°F (30°C), blow air through valve. If air does not pass freely, replace valve. Heat water above 104°F (40°C). No air should pass. If air passes through valve, replace valve.

Fig 1: Subaru Exhaust Gas Recirculation System (Auto. Trans. & 4-WD Models with Hitachi Carbs.)

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