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Home >> Subaru >> 2017 >> WRX STI >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics) (P0171 To P0685) (2.5L) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0411 Secondary Air System Incorrect Flow Detected >> Notes
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DTC P0411 Secondary Air System Incorrect Flow Detected: Notes

DTC DETECTING CONDITION: 

Detected when two consecutive driving cycles with fault occur.

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 SECONDARY AIR COMBINATION VALVE. 
Check the pipe between the secondary air combination valve and cylinder head.
Is there damage or disconnection of the pipe? Replace the pipe between secondary air combination valve and cylinder head. <Ref. to Secondary Air Combination Valve .> Go to step .
2 CHECK SECONDARY AIR COMBINATION VALVE. 
Race the engine at 2, 000 rpm to check whether or not the exhaust leak is heard.
Is there any exhaust leak? Replace the pipe between secondary air combination valve and cylinder head. <Ref. to Secondary Air Combination Valve .> Repair the poor contact of ECM connector.