Exhaust Gas Recirculation (EGR) System Components

1. Remove the EGR valve and inspect it for sticking and excess carbon deposits. If necessary clean the EGR valve with a suitable solvent.

Fig. 188 Testing the EGR valve:

2. Connect a hand vacuum pump to the EGR valve and plug the second nipple, Fig. 188.
3. Apply a vacuum of 67 kPa (20.0 in. Hg) and verify that the control diaphragm chamber is air tight.
4. Verify that when 8 kPa (3 in. Hg) of vacuum is applied to the EGR air does not pass through the valve and that when 23 kPa (7 in. Hg) is applied to the valve air passes through the valve.
5. When the test is complete reinstall the EGR valve using a new gasket and tighten the mounting bolts to 7 - 11 Nm (5 - 8 ft. lbs.).