EGR Backpressure Transducer: Testing and Inspection

1. DISCONNECT VACUUM HOSES FROM EGR VACUUM MODULATOR.
- Disconnect these vacuum hoses:





- Vacuum hose from R port (1).
- Vacuum hose from Q port (2).
- Vacuum hose from P port (3).
2. INSPECT EGR VACUUM MODULATOR OPERATION.





- Block ports P and R with your finger.
- Blow air into port Q, and check that the air passes through to the air filter side freely.
- Start the engine, and maintain speed at 2,500 rpm.





- Repeat the above test.
- Check that there is a strong resistance to air flow.
- If operation is not as specified, replace the EGR vacuum modulator.
3. RECONNECT VACUUM HOSES TO EGR VACUUM MODULATOR.
- Connect these vacuum hoses:





- Vacuum hose to R port (1).
- Vacuum hose to Q port (2).
- Vacuum hose to P port (3).