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EGR Backpressure Transducer: Testing and Inspection


EGR VACUUM MODULATOR INSPECTION





1. DISCONNECT VACUUM HOSES FROM EGR VACUUM MODULATOR
- Disconnect these vacuum hoses:
(1) Vacuum hose from R port
(2) Vacuum hose from Q port
(3) Vacuum hose from P port

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