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Home >> Nissan-Datsun >> 2005 >> Sentra Base, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control System (QG18DE) >> 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
      Fig 1: Checking Harness Connectors & Vacuum Hoses
      G02449611Courtesy of NISSAN MOTOR CO., U.S.A.
    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 2: Identifying Engine Coolant Gauge Indicator Points
      G02449612Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Run engine at about 2, 000 rpm for about 2 minutes under noload.
      Fig 3: Identifying Engine Running At 2000 RPM
      G02449613Courtesy of NISSAN MOTOR CO., U.S.A.
    6. Make sure that no DTC is displayed with CONSULT-II or GST.

    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-II 

    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 noload, then run engine at idle speed for about 1 minute.
      Fig 4: Running Engine At 2000-3000 RPM
      G02449614Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Read idle speed in "DATA MONITOR" mode with CONSULT-II. Refer to DATA MONITOR MODE .
      • M/T: 650 +/- 50 rpm 
      • A/T: 800 +/- 50 rpm (in P or N position) 
      Fig 5: CONSULT-II Display - DATA MONITOR
      G02449615Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

    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: 650 +/- 50 rpm 
      • A/T: 800 +/- 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 or No 

    • 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-II 

    1. Start engine and warm it up to normal operating temperature.
    2. Read idle speed in "DATA MONITOR" mode with CONSULT-II. Refer to IDLE SPEED AND IGNITION TIMING CHECK .
      • M/T: 650 +/- 50 rpm 
      • A/T: 800 +/- 50 rpm (in P or N position) 

    Without CONSULT-II 

    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: 650 +/- 50 rpm 
      • A/T: 800 +/- 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.

    OK or NG 

    • OK : GO TO 9.
    • NG :
      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 "NVIS (NISSAN VEHICLE IMMOBILIZER SYSTEM - NATS) ".
    • : 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 .
      • M/T: 7 +/- 5° BTDC 
      • A/T: 18 +/- 5° BTDC (in P or N position) 
      Fig 6: Identifying Ignition Timing Marks On Crankshaft Pulley
      G02449616Courtesy of NISSAN MOTOR CO., U.S.A.

    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 or No 

    • 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-II 

    1. Start engine and warm it up to normal operating temperature.
    2. Read idle speed in "DATA MONITOR" mode with CONSULT-II. Refer to IDLE SPEED AND IGNITION TIMING CHECK .
      • M/T: 650 +/- 50 rpm 
      • A/T: 800 +/- 50 rpm (in P or N position) 

    Without CONSULT-II 

    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: 650 +/- 50 rpm 
      • A/T: 800 +/- 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 .
      • M/T: 7 +/- 5° BTDC 
      • A/T: 18 +/- 5° BTDC (in P or N position) 
      Fig 7: Identifying Ignition Timing Marks On Crankshaft Pulley
      G02449617Courtesy of NISSAN MOTOR CO., U.S.A.

    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.

    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 "NVIS (NISSAN VEHICLE IMMOBILIZER SYSTEM - NATS) ".
      • : GO TO  4.
  19. INSPECTION END 

    Did you replace ECM, referring this Basic Inspection procedure?

    Yes or No 

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