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EGR Valve: Testing and Inspection



1. Disconnect vacuum hose from upper diaphragm chamber and apply vacuum to valve.
2. Diaphragm should begin to move at approximately 2.4 inches Hg. vacuum, and should reach stop at approximately 11.8 inches Hg. vacuum.
3. Repeat steps 1 and 2 with lower diaphragm chamber.
4. If valve fails to operate properly, valve should be replaced.