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DTC P0400 EGR "A" Flow: Notes

DTC DETECTING CONDITION:

Detected when two consecutive driving cycles with fault occur.

TROUBLE SYMPTOM:

Movement performance problem when engine is low speed
Improper idling
Movement performance problem
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. Start the engine. 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» 53.3 kPa (400 mmHg, 15.75 inHg) or more?	Make sure that the EGR control valve, manifold absolute pressure sensor and throttle body are installed securely.	Go to step 2 .
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 .>