what to do if my Ford F-150 Fourteenth Generation (2021-present) has a P0171 code

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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the vehicle is on a flat surface and engage the parking brake.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to detect leaks around the intake manifold and vacuum lines.
  3. Replace any damaged hoses or gaskets.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the electrical connector.
  3. Remove the MAF sensor from the duct by unscrewing it.
  4. Inspect for dirt or debris; clean with MAF sensor cleaner if necessary or replace if damaged.

4. Check Fuel Pressure

• Sub-steps:
  1. Attach a fuel pressure gauge to the fuel rail.
  2. Turn the ignition to the "ON" position (without starting the engine) and check the pressure reading.
  3. Compare the reading to the manufacturer's specifications (usually between 50-65 psi for most F-150s).
  4. If pressure is low, check the fuel pump and filter for issues and replace as necessary.

5. Check Fuel Injectors

• Sub-steps:
  1. Remove the engine cover if applicable to access the fuel injectors.
  2. Disconnect the electrical connectors from the injectors.
  3. Use a multimeter to test for proper resistance values according to manufacturer specifications.
  4. Clean the injectors using an injector cleaning solution or replace if faulty.