how to fix P0171 code on my Ford F-150 14th Generation (2021-2024)

Learn how to diagnose and fix P0171 engine lean condition in Ford F-150 14th Generation. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Repair Air Intake System

• Sub-steps:
  • Visually inspect the air intake hoses and connections for cracks or disconnections.
  • Replace any damaged hoses.
  • Ensure that the air filter is clean and properly installed.

3. Check and Clean Mass Airflow Sensor (MAF)

• Sub-steps:
  • Locate the MAF sensor on the air intake duct.
  • Disconnect the electrical connector.
  • Remove the MAF sensor using a Torx or socket wrench.
  • Clean the sensor using MAF cleaner (do not use other cleaners).
  • Reinstall the MAF sensor and reconnect the electrical connector.

4. Test Fuel Pressure

• Sub-steps:
  • Locate the fuel pressure test port on the fuel rail.
  • Connect a fuel pressure gauge to the test port.
  • Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading.
  • Compare the reading with manufacturer specifications (typically around 50-60 psi for F-150).
  • If pressure is low, check the fuel pump and fuel filter for issues.

5. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum lines and hoses connected to the intake manifold.
  • Use a smoke machine to detect any vacuum leaks if necessary.
  • Replace any damaged or leaking hoses.

6. Verify Fuel Injector Operation

• Sub-steps:
  • Remove the engine cover (if applicable) to access the fuel injectors.
  • Check for signs of fuel leaks around the injectors.
  • Use a multimeter to test the resistance of each injector to ensure they are within specifications.
  • Replace any faulty injectors.