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Home >> Subaru >> 2017 >> Outback 2.5i >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics) (P0171 To P0685) (H4DO) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0400: EGR "A" Flow >> Notes
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DTC P0400: EGR "A" Flow: Notes

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

Trouble symptom: 

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to OPERATION , Clear Memory Mode, and Inspection Mode Ref. to PROCEDURE , Inspection Mode.
Step Check Yes No
1 CHECK CURRENT DATA. 
  1. Start the engine.
  2. Read the value of «Mani. Absolute Pressure » using the Subaru Select Monitor or a general scan tool.
NOTE:
  • Subaru Select Monitor

    For detailed operation procedures, refer to "Current Data Display For Engine". Ref. to SUBARU SELECT MONITOR

  • General scan tool

For detailed operation procedures, refer to the general scan tool operation manual.
Is the value of «Mani. Absolute Pressure» 1.25 kPa (9.4 mmHg, 0.4 inHg) or more? Make sure that the EGR control valve, manifold absolute pressure sensor and throttle body are installed securely. Go to step
2 CHECK EGR CONTROL VALVE. 
Remove the EGR control valve.
Are there any holes, clogged lines or foreign matters in the EGR system? Repair the EGR system. Replace EGR control valve. Ref. to EGR CONTROL VALVE