how to fix P0171 code on Honda Pilot YF3 (2016-2022)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shock.
• Allow the engine to cool before starting repairs.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses connected to the intake manifold and throttle body.
  • Use a smoke machine or carburetor cleaner to detect leaks.
  • Replace any damaged or cracked hoses.

3. Clean or Replace the MAF Sensor

• Tools Required: MAF sensor cleaner or isopropyl alcohol, soft brush.
• Sub-steps:
  • Locate the MAF sensor in the air intake duct.
  • Disconnect the electrical connector and remove the sensor.
  • Clean the sensor elements carefully with the MAF cleaner.
  • Reinstall the sensor and reconnect the electrical connector.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Sub-steps:
  • Locate the fuel rail and connect the fuel pressure gauge.
  • Turn the ignition to the "ON" position (do not start the engine) and check the fuel pressure.
  • If the pressure is below the specified range (usually around 40-50 psi), consider replacing the fuel pump or checking the fuel filter.

5. Inspect and Clean Fuel Injectors

• Tools Required: Fuel injector cleaner kit.
• Sub-steps:
  • Disconnect the fuel rail from the engine.
  • Remove the fuel injectors.
  • Use the fuel injector cleaner kit to clean each injector.
  • Reinstall the injectors and reconnect the fuel rail.

6. Replace Engine Coolant Temperature Sensor (if faulty)

• Sub-steps:
  • Locate the ECT sensor on the engine block.
  • Disconnect the electrical connector and unscrew the sensor.
  • Install the new sensor and reconnect the electrical connector.