LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Nissan-Datsun >> 2004 >> Sentra Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - QG18DE >> DTC P0171: Fuel Injection System Function >> DTC Confirmation Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC Confirmation Procedure

NOTE: If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

With CONSULT-II 

  1. Start engine and warm it up to normal operating temperature.
  2. Turn ignition switch OFF and wait at least 10 seconds.
  3. Turn ignition switch ON and select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT-II.
  4. Clear the self-learning control coefficient by touching "CLEAR".
  5. Select "DATA MONITOR" mode with CONSULT-II.
  6. Start engine again and let it idle for at least 10 minutes.

    The 1st trip DTC P0171 should be detected at this stage, if a malfunction exists. If so, go to DIAGNOSTIC PROCEDURE .

  7. If it is difficult to start engine at step 6, the fuel injection system has a malfunction.
  8. Crank engine while depressing accelerator pedal. If engine starts, go to DIAGNOSTIC PROCEDURE . If engine does not start, check exhaust gas and intake air leak visually.

With GST 

  1. Start engine and warm it up to normal operating temperature.
  2. Turn ignition switch OFF and wait at least 10 seconds.
  3. Disconnect mass air flow sensor harness connector. Then restart and run engine for at least 5 seconds at idle speed.
  4. Stop engine and reconnect mass air flow sensor harness connector.
  5. Select MODE 3 with GST. Make sure DTC P0102 is detected.
  6. Select MODE 4 with GST and erase the DTC P0102.
  7. Start engine again and run it for at least 10 minutes at idle speed.
  8. Select MODE 7 with GST. The 1st trip DTC P0171 should be detected at this stage, if a malfunction exists. If so, go to DIAGNOSTIC PROCEDURE .
  9. If it is difficult to start engine at step 7, the fuel injection system has a malfunction.
  10. Crank engine while depressing accelerator pedal. If engine starts, go to DIAGNOSTIC PROCEDURE . If engine does not start, check exhaust gas and intake air leak visually.
    Fig 1: Identifying Mass Air Flow Sensor Harness Connector
    G00772727Courtesy of NISSAN MOTOR CO., U.S.A.