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P0400







P0400-EGR SYSTEM FLOW MALFUNCTION





For a complete wiring diagram Refer to Diagrams/Electrical.

Theory of Operation

This diagnostic monitors EGR position when it is commanded closed.
- When Monitored:
Engine running, EGR valve commanded closed.

- Set Condition:
Detected EGR position is greater than 6% for more than 2 seconds.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview


Diagnostic Test


1. OTHER DTC'S
Ignition on, engine not running.
With the scan tool, read DTC's.
Are there other DTC's?

Yes


- Troubleshoot other DTC's first.


No


- Replace EGR valve.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test .