EGR Valve Inspection
1. Remove the EGR valve and check it for sticking, carbon deposits, etc. If necessary clean the EGR valve with a suitable solvent.
2. Connect a hand vacuum pump to the EGR valve.
3. Apply a vacuum of 500mm Hg (19.8 in. Hg) and verify that the diaphragm chamber is leak tight.
4. Apply 45 mm Hg (1.8 in. Hg) of vacuum to the valve and verify that air does not pass through the EGR valve.
5. Increase vacuum to 230 mm Hg (9.1 in. Hg) and verify that air will pass through the EGR valve.
6. Re-install the EGR valve when testing is complete and tighten the mounting bolts to 22 Nm (16 ft.lbs).