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DTC P0400

DTC P0400  : EGR System Leak Detected

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems .

DTC Description Confirmed DTC Pending DTC Freeze Frame
P0400 EGR System Leak Detected      

DTC (PGM-FI)

  1. EGR pipe visual check

    - 1. Check for a loose or damaged EGR pipe.

    Is the EGR pipe OK?

    YES 

    Go to step 2.

    NO 

    Reconnect or replace the EGR pipe .

  2. Problem verification

    - 1. Start the engine.

    - 2. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.

    - 3. Test-drive under these conditions:

    • Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
    • Transmission in D
    • Drive the vehicle below 25 mph (40 km/h) for 5 minutes or more
    • Maintain the vehicle speed at 26 mph (41 km/h) or more and the engine speed between 1, 400-3, 000 rpm for 10 seconds or more with cruise control set
    Signal Current conditions
    Values Unit
    ECT SENSOR 1    
    VEHICLE SPEED    
    ENGINE SPEED    

    - 4. Monitor the OBD STATUS for DTC P0400 in the DTCs MENU with the HDS.

    DTC Description OBD STATUS
    P0400 EGR System Leak Detected  

    Does the HDS indicate FAILED?

    YES 

    Replace the EGR valve .

    NO 

    If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check for leakage between the EGR pipe and the EGR valve. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot - Refer to: How to Troubleshoot the Fuel and Emissions Systems . If the HDS indicates NOT COMPLETED, go to step 2-3 and recheck.