Vacuum Supply Test

EGR Vacuum Control Check:

NOTE: Coolant temperature should be: 80-95°C (176-203°F), for this test.

1. Disconnect the vacuum hose from the throttle body EGR vacuum nipple and connect a hand vacuum pump or gauge to the nipple.
2. Start the engine. Gradually increase the engine RPM. Vacuum from the EGR nipple should increase proportionately with the engine RPM.

NOTE: If vacuum cannot be measured or does not change with the engine RPM ensure that the hose is connected to the proper port. If so the EGR port may be plugged and should be cleaned.