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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 Refer to ENGINE (DIAGNOSTICS) (STI)>CLEAR MEMORY MODE>OPERATION ., and inspection mode Refer to ENGINE (DIAGNOSTICS) (STI)>INSPECTION MODE>PROCEDURE .
  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?

    Yes:  Replace the pipe between secondary air combination valve and cylinder head. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (STI)>SECONDARY AIR COMBINATION VALVE .

    No:  Go to  2.

  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?

    Yes:  Replace the pipe between secondary air combination valve and cylinder head. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (STI)>SECONDARY AIR COMBINATION VALVE .

    No:  Repair the poor contact of ECM connector.