how to fix P0171 code on Ford F-150 Fourteenth Generation (2021-present)

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 all necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety while working on electrical components.

2. Inspect and Repair Air Intake System

• Tools Required: Socket set, screwdrivers.
• Remove the air intake duct and inspect it for cracks or loose connections.
• If any damage is found, replace the duct with a new one.
• Reinstall the duct and ensure all connections are secure.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, Torx screwdriver.
• Remove the MAF sensor from the air intake system.
• Spray the MAF sensor with MAF cleaner, avoiding contact with the sensor element.
• Allow it to dry completely before reinstalling. If cleaning does not resolve the issue, replace the sensor with a new one.

4. Inspect and Replace Vacuum Lines

• Tools Required: Pliers, vacuum line replacement kit.
• Visually inspect all vacuum lines for cracks or loose connections.
• Replace any damaged lines with new vacuum hoses.

5. Check and Repair Fuel System

• Tools Required: Fuel pressure gauge, wrench set.
• Connect the fuel pressure gauge to the fuel rail and turn the ignition to the "ON" position (do not start the engine).
• Check the fuel pressure; it should be within manufacturer specifications (consult service manual for exact values).
• If pressure is low, inspect the fuel pump, filter, and fuel injectors for issues and replace as necessary.

6. Clear Codes and Test Drive

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0171 code.
• Test drive the vehicle to ensure that the check engine light does not reappear and that the vehicle runs smoothly.