EGR Backpressure Transducer: Testing and Inspection

EGR VACUUM MODULATOR INSPECTION

1. Disconnect vacuum hoses from EGR vacuum modulator.
- Disconnect the 3 vacuum hoses from ports P, Q and R of the EGR vacuum modulator.
2. Inspect EGR vacuum modulator operation.

Engine Off:

- Block ports P and R with your finger.
- Blow air into port Q, and check that air passes through to the air filter side freely.
- Start the engine, and maintain speed at 3,500 rpm.

Engine At 3,500 RPM:

- Repeat the above test.
- Check that there is a strong resistance to air flow.
3. Reconnect vacuum hoses to EGR vacuum modulator.
- Connect the 3 vacuum hoses to the proper locations.