System Operational Test
EGR Vacuum Delivery Test:
1. Disconnect the green striped vacuum hose from the EGR valve and connect a hand vacuum pump through a 3-way vacuum "Tee".
2. While the engine is cold [coolant temperature less than 20° C(68°F)] race the engine and verify that vacuum is not present.
3. Allow the engine to warm up [coolant temperature greater than 70° C(158° F)].
4. Race the engine and verify that vacuum increases to 100 mm (3.9 in.)Hg or more.
EGR Valve Inspection:
5. Disconnect the vacuum "Tee" and connect the vacuum pump directly to the EGR valve.
6. Using the vacuum pump, apply 100mm(3.9 in.) Hg of vacuum while the engine is at idle and verify that idle becomes unstable or the engine stalls.