Federal Spec. Vehicles

VSV INSPECTION PROCEDURE
1. REMOVE THE VACUUM SWITCHING VALVE (VSV).
a. Disconnect the following connectors and hoses.



1. VSV connector.
2. Vacuum hose (from EGR valve) from port E of VSV.
3. Vacuum hose (from port Q of EGR vacuum modulator) from port G of VSV.
b. Remove the bolt and the VSV assembly.

2. INSPECT VSV FOR AN OPEN CIRCUIT.



- Using an ohmmeter. check that there is continuity between the terminals.

Resistance: 33 - 39 Ohms at 20°C (68°F)

- If there is no continuity, replace the VSV.

3. INSPECT VSV FOR GROUND.



- Using an ohmmeter. check that there is NO continuity between each terminal and the body.
- If there is continuity, replace the VSV.

4. INSPECT VSV OPERATION.



- Check that the air flows from ports E to G.



- Apply battery voltage across the terminals.
- Check that the air flows from port E to the filter.
- If operation is not as specified, replace the VSV.

5. REINSTALL VSV.
- Reconnect connectors and hoses.