System Check

Fig. 7 Checking EGR valve diaphragm:

Fig. 8 Checking movement of EGR diaphragm:

1. With engine running and coolant temperature below 131°F (55°C), check that EGR valve is not open by feeling diaphragm with finger, Fig. 7.
2. Allow engine to reach normal operating temperature. Race engine and check that diaphragm moves toward 1, Fig. 8, during acceleration and toward 2 during deceleration.