EGR Backpressure Transducer: Testing and Inspection

Fig. 14 EGR Vacuum Modulator Filters:

1. Remove the top cap from the EGR vacuum modulator and remove the air filters. Fig. 14
2. Check the filters for contamination or damage. Replace if necessary.
3. Reinstall the filters and the top cap.

Fig. 29 Testing Vacuum Modulator:

4. Disconnect the vacuum hoses from ports P, Q and R of the EGR vacuum modulator.
5. Block ports P and R with your finger, while blowing air into port Q. Fig. 29
6. Check that air passes through air filter side freely.
7. Start the engine and maintain speed at 3,000 rpm.

Fig. 30 Testing Vacuum Modulator:

8. Repeat step 5. There should be strong resistance to air flow through the air filter side. Fig. 30
9. If a problem is found, replace the vacuum modulator.
10. Reconnect the vacuum hoses to their proper locations.