LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2004 >> M45 >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Engine Control System >> Basic Service Procedure >> Fuel Pressure Check >> Fuel Pressure Release >> Fuel Pressure Check
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Fuel Pressure Check

Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger. 

NOTE:
  • Use Fuel Pressure Gauge Kit (J-44321) to check fuel pressure.
  • Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel pressure cannot be released because Y34 models do not have fuel return system.
  1. Release fuel pressure to zero. Refer to FUEL PRESSURE RELEASE .
  2. Install the inline fuel quick disconnected fitting between fuel damper and injector tube.
    Fig 1: Installing Fuel Pressure Gauge Kit
    G00795518Courtesy of NISSAN MOTOR CO., U.S.A.
  3. Connect the fuel pressure test gauge (quick connector adapter hose) to the inline fuel quick disconnected fitting.
    Fig 2: Connecting Fuel Pressure Gauge Kit
    G00795519Courtesy of NISSAN MOTOR CO., U.S.A.
  4. Turn ignition switch ON and check for fuel leakage.
  5. Start engine and check for fuel leakage.
  6. Read the indication of fuel pressure gauge.

    At idling: Approximately 350 kPa (3.57  kg/cm2 , 51 psi)

  7. If result is unsatisfactory, go to next step.
  8. Check the following.
    • Fuel hoses and fuel tubes for clogging
    • Fuel filter for clogging
    • Fuel pump
    • Fuel pressure regulator for clogging

      If OK, replace fuel pressure regulator.

      If NG, repair or replace.