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Detailed Procedure

  1. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2" 
    1. Start engine.
    2. Confirm that the testing conditions are met. Refer to "TESTING CONDITION ".
    3. Select "A/F ALPHA-B1", "A/F ALPHA-B2" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.
      NOTE: Check "A/F ALPHA-B1", "A/F ALPHA-B2" for approximately 1 minute because they may fluctuate. It is NG if the indication is out of the SP value even a little.

    OK or NG 

    1. OK: GO TO  14
    2. NG (Less than the SP value): GO TO 2.
    3. NG (More than the SP value): GO TO  3
      Fig 1: A/F Alpha-B1 A/F Alpha-B2 Display
      G02372643Courtesy of NISSAN MOTOR CO., U.S.A.
  2. CHECK "B/FUEL SCHDL" 

    Select "B/FUEL SCHDL" in "DATA MONITOR (SPEC)" mode, and make sure that the indication is within the SP value.

    OK or NG 

    1. OK: GO TO  4.
    2. NG (More than the SP value): GO TO  16
    Fig 2: B/Fuel SCHDL Display (1 Of 2)
    G02372644Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK "B/FUEL SCHDL" 

    Select "B/FUEL SCHDL" in "DATA MONITOR (SPEC)" mode, and make sure that the indication is within the SP value.

    OK or NG 

    1. OK: GO TO  3.
    2. NG (More than the SP value): GO TO  3.
    3. NG (Less than the SP value): GO TO  22.
    Fig 3: B/Fuel SCHDL Display (2 Of 2)
    G02372645Courtesy of NISSAN MOTOR CO., U.S.A.
  4. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2" 
    1. Stop the engine.
    2. Disconnect PCV hose, and then plug it.
    3. Start engine.
    4. Select "A/F ALPHA-B1", "A/F ALPHA-B2" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

    OK or NG 

    1. OK: GO TO 5.
    2. NG: GO TO  3.
  5. CHANGE ENGINE OIL 
    1. Stop the engine.
    2. Change engine oil.
      NOTE: This symptom may occur when a large amount of gasoline is mixed with engine oil because of driving conditions (such as when engine oil temperature does not rise enough since a journey distance is too short during winter). The symptom will not be detected after changing engine oil or changing driving condition.
      1. INSPECTION END 
    3. CHECK FUEL PRESSURE 

      Check fuel pressure. (Refer to "FUEL PRESSURE CHECK ".)

      OK or NG 

      1. OK: GO TO  11.
      2. NG (Fuel pressure is too high): Replace fuel pressure regulator, Refer to DIAGNOSTIC PROCEDURE , GO TO  5.
      3. NG (Fuel pressure is too low): GO TO 7.
    4. DETECT MALFUNCTIONING PART 
      1. Check the following.
        • Clogged and bent fuel hose and fuel tube
        • Clogged fuel filter
        • Fuel pump and its circuit (Refer to FUEL PUMP CIRCUIT .)
      2. If NG, repair or replace the malfunctioning part. (Refer to DIAGNOSTIC PROCEDURE .) If OK, replace fuel pressure regulator.
        1. GO TO 8.
    5. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2" 
      1. Start engine.
      2. Select "A/F ALPHA-B1", "A/F ALPHA-B2" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG: GO TO 9.
    6. PERFORM POWER BALANCE TEST 
      1. Perform "POWER BALANCE" in "ACTIVE TEST" mode.
      2. Make sure that the each cylinder produces a momentary engine speed drop.

      OK or NG 

      1. OK: GO TO  9.
      2. NG: GO TO 10.
      Fig 4: Power Balance Display
      G02372646Courtesy of NISSAN MOTOR CO., U.S.A.
    7. DETECT MALFUNCTIONING PART 
      1. Check the following.
      2. If NG, repair or replace the malfunctioning part.

        If OK, replace fuel injector. (It may be caused by leakage from fuel injector or clogging.)

        1. GO TO 11.
    8. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2" 
      1. Start engine.
      2. Select "A/F ALPHA-B1", "A/F ALPHA-B2" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG: GO TO 12.
    9. CHECK HEATED OXYGEN SENSOR 1 FUNCTION 
      1. Run engine at about 2, 000 rpm for about 2 minutes under no-load.
      2. Select "HO2S1 MNTR (B1)", "HO2S1 MNTR (B2)" in "DATA MONITOR" mode.
      3. Running engine at 2, 000 rpm under no-load (The engine is warmed up to normal operating temperature.), check that the monitor fluctuates between LEAN and RICH more than 5 times during 10 seconds.
        1. 1 time: RICH --> LEAN --> RICH 
        2. 2 time: RICH --> LEAN --> RICH --> LEAN --> RICH 
        Fig 5: Ho2S1 MNTR (B1) Display
        G02372647Courtesy of NISSAN MOTOR CO., U.S.A.

      OK or NG 

      1. OK: GO TO  12.
      2. NG: GO TO 13.
    10. CHECK HEATED OXYGEN SENSOR 1 CIRCUIT 

      Check heated oxygen sensor 1 and its circuit. Refer to DTC P0132, P0152 HO2S1 .

      1. GO TO 14.
    11. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2" 
      1. Start engine.
      2. Select "A/F ALPHA-B1", "A/F ALPHA-B2" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG: GO TO 15.
    12. DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR 
      1. Stop the engine.
      2. Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.
        1. GO TO 16.
    13. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2" 
      1. Start engine.
      2. Select "A/F ALPHA-B1", "A/F ALPHA-B2" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG: Detect malfunctioning part according to " SYMPTOM MATRIX CHART  "  .
    14. CHECK "B/FUEL SCHDL" 

      Select "B/FUEL SCHDL" in "DATA MONITOR (SPEC)" mode, and make sure that the indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG (More than the SP value): GO TO 18.
      3. NG (Less than the SP value): GO TO  22.
      Fig 6: B/Fuel SCHDL Display
      G02372648Courtesy of NISSAN MOTOR CO., U.S.A.
    15. DETECT MALFUNCTIONING PART 
      1. Check for the cause of large engine friction. Refer to the following.
        • Engine oil level is too high
        • Engine oil viscosity
        • Belt tension of power steering, alternator, A/C compressor, etc. is excessive
        • Noise from engine
        • Noise from transmission, etc.
      2. Check for the cause of insufficient combustion. Refer to the following.
        • Valve clearance malfunction
        • Intake valve timing control function malfunction
        • Camshaft sprocket installation malfunction, etc.
          1. Repair or replace malfunctioning part, and then GO TO 30.
    16. CHECK INTAKE SYSTEM 

      Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.

      • Crushed air ducts
      • Malfunctioning seal of air cleaner element
      • Uneven dirt of air cleaner element
      • Improper specification of intake air system

      OK or NG 

      1. OK: GO TO  18.
      2. NG: Repair or replace malfunctioning part, and then GO TO 20.
    17. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2", AND "B/FUEL SCHDL" 

      Select "A/F ALPHA-B1", "A/F ALPHA-B2", and "B/FUEL SCHDL" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG ("B/FUEL SCHDL" is more, "A/F ALPHA-B1", "A/F ALPHA-B2" are less than the SP value): GO TO 21.
    18. DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR 
      1. Stop the engine.
      2. Disconnect mass air flow sensor harness connector. Check pin terminal and connector for damage and then reconnect it again.
      1. GO TO 22.
    19. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2" 
      1. Start engine.
      2. Select "A/F ALPHA-B1", "A/F ALPHA-B2" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

      OK or NG 

      1. OK:
        1. Detect malfunctioning part of mass air flow sensor circuit and repair it. Refer to DTC P0102, P0103 MAF SENSOR .
        2. GO TO  26.
      2. NG: GO TO 23.
    20. CHECK "MAS A/F SE-B1" 

      Select "MAS A/F SE-B1" in "DATA MONITOR (SPEC)" mode, and make sure that the indication is within the SP value.

      OK or NG 

      OK: GO TO 24.

      NG (More than the SP value): Replace mass air flow sensor, and then GO TO  26.

      Fig 7: MAS A/F Se-B1 Display
      G02372649Courtesy of NISSAN MOTOR CO., U.S.A.
    21. REPLACE ECM 
      1. Replace ECM.
      2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs. Refer to "ECM RE-COMMUNICATING FUNCTION ".
      3. Perform "VIN REGISTRATION ".
      4. Perform "ACCELERATOR PEDAL RELEASED POSITION LEARNING ".
      5. Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".
      6. Perform "IDLE AIR VOLUME LEARNING ".
        1. GO TO  26.
    22. CHECK INTAKE SYSTEM 

      Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.

      • Crushed air ducts
      • Malfunctioning seal of air cleaner element
      • Uneven dirt of air cleaner element
      • Improper specification of intake air system

      OK or NG 

      1. OK: GO TO  24.
      2. NG: Repair or replace malfunctioning part, and then GO TO 26.
    23. CHECK "B/FUEL SCHDL" 

      Select "B/FUEL SCHDL" in "DATA MONITOR (SPEC)" mode, and make sure that the indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG (Less than the SP value): GO TO 27.
    24. CHECK "MAS A/F SE-B1" 

      Select "MAS A/F SE-B1" in "DATA MONITOR (SPEC)" mode, and make sure that the indication is within the SP value.

      OK or NG 

      1. OK: GO TO 28.
      2. NG (Less than the SP value): Replace mass air flow sensor, and then GO TO  27.
      Fig 8: MAS A/F Se-B1 Display
      G02372650Courtesy of NISSAN MOTOR CO., U.S.A.
    25. CHECK INTAKE SYSTEM 

      Check for the cause of air leak after the mass air flow sensor. Refer to the following.

      • Disconnection, looseness, and cracks in air duct
      • Looseness of oil filler cap
      • Disconnection of oil level gauge
      • Open stuck, breakage, hose disconnection, or cracks of PCV valve
      • Disconnection or cracks of EVAP purge hose, open stuck of EVAP canister purge volume control solenoid valve
      • Malfunctioning seal of rocker cover gasket
      • Disconnection, looseness, or cracks of hoses, such as vacuum hose, connecting to intake air system parts
      • Malfunctioning seal of intake air system, etc.
        1. GO TO  27.
    26. CHECK "A/F ALPHA-B1", "A/F ALPHA-B2", AND "B/FUEL SCHDL" 

      Select "A/F ALPHA-B1", "A/F ALPHA-B2", and "B/FUEL SCHDL" in "DATA MONITOR (SPEC)" mode, and make sure that the each indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG: Detect malfunctioning part according to " SYMPTOM MATRIX CHART  "  .
    27. CHECK "B/FUEL SCHDL" 

      Select "B/FUEL SCHDL" in "DATA MONITOR (SPEC)" mode, and then make sure that the indication is within the SP value.

      OK or NG 

      1. OK: INSPECTION END 
      2. NG: Detect malfunctioning part according to " SYMPTOM MATRIX CHART  "  .
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