EGR Backpressure Transducer: Testing and Inspection

EGR VACUUM MODULATOR INSPECTION:
- Disconnect the vacuum hoses from ports P, Q and R of the EGR vacuum modulator.



- Block ports P and R with your finger.
- Blow air into port Q.
- Check that the 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.
- Reconnect the vacuum hoses to the proper locations.