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Home >> Infiniti >> 2004 >> QX56 RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System >> DTC P0171, P0174: Fuel Injection System Function >> DTC Confirmation Procedure >> With GST
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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 let it idle for at least 10 minutes.
  8. Select MODE 7 with GST. The 1st trip DTC P0171 or P0174 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 and intake air leak visually.
    Fig 1: Locating Mass Air Flow Sensor With Intake Air Temperature Sensor
    G02691312Courtesy of NISSAN MOTOR CO., U.S.A.