Thermal Vacuum Valve: Testing and Inspection

Fig. 33 Thermo Vacuum Valve:

1. Remove the vacuum hose from the angled connector (vacuum source) of the thermo-vacuum valve, Fig. 33.
2. Remove the vacuum hose from the EGR valve.
3. Blow through the hose. The hose should be:
Open with coolant temperature below 45°C (113°F)
Closed above 61°C (142°F)
NOTE: If necessary, remove the thermo vacuum switch and heat or cool down with water to test.