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Home >> Nissan-Datsun >> 2012 >> Sentra SL >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Introduction (MR20DE) (CALIFORNIA) >> Service Information >> Basic Service Procedure >> Basic Inspection
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Basic Inspection

  1. INSPECTION START
    1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for scheduled maintenance.
    2. Open engine hood and check the following:
      • Harness connectors for improper connections
      • Wiring harness for improper connections, pinches and cut
      • Vacuum hoses for splits, kinks and improper connections
      • Hoses and ducts for leaks
      • Air cleaner clogging
      • Gasket
    3. Confirm that electrical or mechanical loads are not applied.
      • Headlamp switch is OFF.
      • Air conditioner switch is OFF.
      • Rear window defogger switch is OFF.
      • Steering wheel is in the straight-ahead position, etc.
    4. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.

      Ensure engine stays below 1, 000 rpm.

      Fig 1: Checking Harness Connectors For Improper Connections And Vacuum Hoses For Splits
      G04874817Courtesy of NISSAN NORTH AMERICA, INC.
      Fig 2: Identifying Engine Coolant Temperature Indicator Points
      G04874818Courtesy of NISSAN NORTH AMERICA, INC.
    5. Run engine at about 2, 000 rpm for about 2 minutes under no load.
    6. Make sure that no DTC is displayed with CONSULT or GST.
    Fig 3: Identifying Engine rpm Indicator
    G04874819Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO  3.

    NG: GO TO 2.

  2. REPAIR OR REPLACE

    Repair or replace components as necessary according to corresponding Diagnostic Procedure.

    GO TO 3.

  3. CHECK TARGET IDLE SPEED

    With CONSULT

    1. Run engine at about 2, 000 rpm for about 2 minutes under no load.
    2. Rev engine (2, 000 to 3, 000 rpm) two or three times under no load, then run engine at idle speed for about 1 minute.
      Fig 4: Identifying Idle Speed (2, 000 To 3, 000 rpm)
      G04900035Courtesy of NISSAN NORTH AMERICA, INC.
    3. Read idle speed in "DATA MONITOR" mode with CONSULT. Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

      M/T: 675 ± 50 rpm (in Neutral position) 

      CVT: 700 ± 50 rpm (in P or N position) 

      Without CONSULT

    1. Run engine at about 2, 000 rpm for about 2 minutes under no load.
    2. Rev engine (2, 000 to 3, 000 rpm) two or three times under no load, then run engine at idle speed for about 1 minute.
    3. Check idle speed. Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

      M/T: 675 ± 50 rpm (in Neutral position) 

      CVT: 700 ± 50 rpm (in P or N position) 

      OK or NG 

      OK: GO TO  10.

      NG: GO TO 4.

  4. PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
    1. Stop engine.
    2. Perform "ACCELERATOR PEDAL RELEASED POSITION LEARNING ".

      GO TO 5.

  5. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

    Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".

    GO TO 6.

  6. PERFORM IDLE AIR VOLUME LEARNING

    Refer to "IDLE AIR VOLUME LEARNING ".

    Is Idle Air Volume Learning carried out successfully? 

    YES: GO TO 7.

    NO:

    1. Follow the instruction of Idle Air Volume Learning.
    2. GO TO  4.
  7. CHECK TARGET IDLE SPEED AGAIN

    With CONSULT

    1. Start engine and warm it up to normal operating temperature.
    2. Read idle speed in "DATA MONITOR" mode with CONSULT. Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

      M/T: 675 ± 50 rpm (in Neutral position) 

      CVT: 700 ± 50 rpm (in P or N position) 

      Without CONSULT

    1. Start engine and warm it up to normal operating temperature.
    2. Check idle speed. Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

    M/T: 675 ± 50 rpm (in Neutral position) 

    CVT: 700 ± 50 rpm (in P or N position) 

    OK or NG 

    OK: GO TO  10.

    NG: GO TO 8.

  8. DETECT MALFUNCTIONING PART

    Check the following.

    1. Repair or replace.
    2. GO TO  4.
  9. CHECK ECM FUNCTION
    1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but this is a rare case.)
    2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs. Refer to , "ECM RE-COMMUNICATING FUNCTION ".

    GO TO  4.

  10. CHECK IGNITION TIMING
    1. Run engine at idle.
    2. Check ignition timing with a timing light.

      Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

      • Timing indicator (1)

    M/T: 6 ± 5° BTDC (in Neutral position) 

    CVT: 6 ± 5° BTDC (in P or N position) 

    Fig 5: Checking Ignition Timing Using Timing Indicator
    G04925134Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO  19.

    NG: GO TO 11.

  11. PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
    1. Stop engine.
    2. Perform "ACCELERATOR PEDAL RELEASED POSITION LEARNING ".

    GO TO 12.

  12. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

    Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".

    GO TO 13.

  13. PERFORM IDLE AIR VOLUME LEARNING

    Refer to "IDLE AIR VOLUME LEARNING ".

    Is Idle Air Volume Learning carried out successfully? 

    YES: GO TO 14.

    NO:

    1. Follow the instruction of Idle Air Volume Learning.
    2. GO TO  4.
  14. CHECK TARGET IDLE SPEED AGAIN

    With CONSULT

    1. Start engine and warm it up to normal operating temperature.
    2. Read idle speed in "DATA MONITOR" mode with CONSULT. Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

    M/T: 675 ± 50 rpm (in Neutral position) 

    CVT: 700 ± 50 rpm (in P or N position) 

    Without CONSULT

    1. Start engine and warm it up to normal operating temperature.
    2. Check idle speed. Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

    M/T: 675 ± 50 rpm (in Neutral position) 

    CVT: 700 ± 50 rpm (in P or N position) 

    OK or NG 

    OK: GO TO 15.

    NG: GO TO  17.

  15. CHECK IGNITION TIMING AGAIN
    1. Run engine at idle.
    2. Check ignition timing with a timing light.

    Refer to "IDLE SPEED AND IGNITION TIMING CHECK ".

    • Timing indicator (1)

    M/T: 6 ± 5° BTDC (in Neutral position) 

    CVT: 6 ± 5° BTDC (in P or N position) 

    Fig 6: Checking Ignition Timing Using Timing Indicator
    G04925134Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO  19

    NG: GO TO 16.

  16. CHECK TIMING CHAIN INSTALLATION

    Check timing chain installation. Refer to TIMING CHAIN .

    OK or NG 

    OK: GO TO 17.

    NG:

    1. Repair the timing chain installation.
    2. GO TO  4.
  17. DETECT MALFUNCTIONING PART

    Check the following.

    • Check crankshaft position sensor (POS) and circuit.

      Refer to DTC P0335 CKP SENSOR (POS) .

    • Check camshaft position sensor (PHASE) and circuit.

    Refer to DTC P0340 CMP SENSOR (PHASE) .

    OK or NG 

    OK: GO TO 18.

    NG:

    1. Repair or replace.
    2. GO TO  4.
  18. CHECK ECM FUNCTION
    1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but this is a rare case.)
    2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.

    Refer to , "ECM RE-COMMUNICATING FUNCTION ".

    GO TO  4.

  19. INSPECTION END

    Did you replace ECM, referring this Basic Inspection procedure?

    YES or NO 

    YES:

    1. Perform "VIN REGISTRATION ".
    2. INSPECTION END 

    NO: INSPECTION END 

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