Thermal Vacuum Valve - EVAP: Testing and Inspection

Remove or Disconnect

1. Negative (-) battery cable.

^ Drain engine coolant.

2. Two vacuum hoses from evaporative emission thermal vacuum valve (EVAP TVV).

EVAP Thermal Vacuum Valve:

3. EVAP TVV from intake manifold.

Inspect

^ EVAP TVV for proper operation.

Testing EVAP TVV:

^ Cool EVAP TVV by placing in water and cooling to 35° C (95° F). Check the air does not flow from the upper port to the lower port. If operation is not as specified replace EVAP TVV.

Testing EVAP TVV - 54 Degrees C:

^ Heat EVAP TVV by placing in water and heating to 54° C (129° F). Check that air flows from the upper port to the lower port. If operation is not as specified, replace EVAP TVV.

Install or Connect

1. Apply RTV SILICON SEALANT, GM P/N 105297, or equivalent to two or three threads of EVAP TVV.

2. EVAP TVV to intake manifold.

3. Two vacuum hoses to EVAP TVV.

^ Refill engine coolant to proper level.

4. Negative (-) battery cable.

Tighten

^ Negative (-) battery cable-to-negative (-) battery terminal retainer to 15 Nm (11 lb.ft.).