2004 Infiniti FX45FACTORY OEM SERVICE PROCEDURE

Diagnostic Procedure

  1. Check Intake Air Leak 
    1. Start engine and let it idle.
    2. Listen for an intake air leak after the mass air flow sensor.

    OK or NG

    1. OK: go to 2.
    2. NG: Discover air leak location and repair.

  2. Replace ECM 
    1. Stop engine.
    2. Replace ECM.
    3. Perform initialization of NATS system and registration of all NATS ignition key IDs. Refer to ECM RE-COMMUNICATING FUNCTION .
    4. Perform ACCELERATOR PEDAL RELEASED POSITION LEARNING  .
    5. Perform THROTTLE VALVE CLOSED POSITION LEARNING  .
    6. Perform IDLE AIR VOLUME LEARNING  .
      1. Inspection end 
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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