Thermal Vacuum Valve - EVAP: Testing and Inspection

1. When engine is cold (less than 58° C or 136° F), disconnect a vacuum hose at the Thermo Vacuum Valve. Blow through the valve. The valve should be closed and air stream should be blocked.
2. Reconnect vacuum hose and run engine to operating temperature (above 58° C or 136° F).
3. Disconnect the vacuum hose again and blow through the Thermo Vacuum Valve. The valve should now be open and air stream should be unrestricted.
4. If valve fails any of the tests above, replace and retest with new valve.
5. Reconnect the vacuum hose.