how to fix P0171 code on Honda Pilot YF4 (2023-Present)

Solution

1. Preparation

• Gather tools and parts required for the repair. Ensure the vehicle is parked on a level surface.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down before starting work.

2. Inspect and Repair Vacuum Leaks

• Inspect hoses and gaskets:
  • Visually examine all vacuum hoses for cracks, disconnections, or wear.
  • Check the intake manifold gasket for signs of leakage.
• Repair or replace:
  • Replace any damaged hoses or gaskets with OEM parts.

3. Clean or Replace MAF Sensor

• Remove MAF sensor:
  • Disconnect the electrical connector and unscrew the MAF sensor from the air intake.
• Clean MAF sensor:
  • Use MAF sensor cleaner to spray the sensing element gently. Allow it to dry completely.
• Replace if necessary:
  • If the sensor is damaged or cleaning doesn't resolve issues, replace it with a new one.

4. Test Fuel System

• Check fuel pressure:
  • Connect a fuel pressure gauge to the fuel rail Schrader valve.
  • Turn the ignition to the ON position (do not start) and check the pressure reading against specifications.
• Replace fuel filter or pump:
  • If pressure is low, consider replacing the fuel filter or fuel pump as needed.

5. Inspect and Clean Fuel Injectors

• Remove fuel injectors:
  • Disconnect the fuel rail and gently pull out the injectors.
• Clean or replace:
  • Use a fuel injector cleaning kit to clean or replace the injectors if clogged.

6. Check Oxygen Sensors

• Inspect and test:
  • Check the wiring and connectors of the upstream oxygen sensor.
  • Use a multimeter to test the sensor's voltage output according to the specifications.
• Replace if faulty:
  • Replace the sensor if it is not functioning correctly.