Vacuum Amplifier: Testing and Inspection

1. On a cold engine, disconnect vacuum hoses from ports P and Q from vacuum modulator.
2. Plug port P. Blow into port Q and ensure air passes through the air filter side freely.
3. Plug disconnected vacuum hoses and start engine.
4. Warm engine and idle at 3000 RPM.
5. Repeat steps 2. Ensure a strong resistance to air flow.
6. If any test fails, replace the EGR vacuum modulator.