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Home >> Infiniti >> 2021 >> Q50 Pure, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS) (2 Of 6) >> Engine (ECM) >> P0171 Fuel Injection System Function >> Confirmation Procedure >> VR30DDTT engine
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VR30DDTT engine

  1. PRECONDITIONING 

    If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.

    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Turn ignition switch ON.
    3. Turn ignition switch OFF and wait at least 10 seconds.

    GO TO 2.

  2. PERFORM DTC CONFIRMATION PROCEDURE-I 
    1. Clear the mixture ratio self-learning value. Refer to Work Procedure .
    2. Start engine.

    Is it difficult to start engine?

    YES

    GO TO 3.

    NO

    GO TO 4.

  3. RESTART ENGINE 

    If it is difficult to start engine, the fuel injection system has a malfunction, too.

    Crank engine while depressing accelerator pedal.

    NOTE: When depressing accelerator pedal three fourths (3/4) or more, the control system does not start the engine.

    Do not depress accelerator pedal too much.

    Does engine start?

    YES

    Refer to DTC Diagnosis Procedure .

    NO

    Check exhaust and intake air leak visually.

  4. PERFORM DTC CONFIRMATION PROCEDURE-II 
    1. Keep engine idle for at least 5 minutes.
    2. Check 1st trip DTC.

    Is 1st trip DTC detected?

    YES

    Refer to DTC Diagnosis Procedure .

    NO

    GO TO 5.

  5. PERFORM DTC CONFIRMATION PROCEDURE-III 
    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Start engine.
    3. Maintain the following conditions for at least 10 consecutive minutes.

      Hold the accelerator pedal as steady as possible.

      VHCL SPEED SE

      50 - 120 km/h (31 - 75 MPH)

      CAUTION: Always drive vehicle at a safe speed.
    4. Check 1st trip DTC.

    Is 1st trip DTC detected?

    YES

    Refer to DTC Diagnosis Procedure .

    NO

    To check malfunction symptom before repair: Refer to Inspection .

    NO

    Confirmation after repair: INSPECTION END