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

Learn how to diagnose and fix P0171 fuel system issue in Ford F-150 (2021-2024). Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down.

2. Inspect and Repair Air Intake System

• Tools Required: Screwdrivers, pliers, flashlight
• Check for any visible cracks or loose connections in the air intake hoses and replace if necessary.
• Ensure the air filter is clean and replace it if needed.

3. Clean the MAF Sensor

• Tools Required: MAF sensor cleaner spray, soft cloth
• Carefully remove the MAF sensor from the air intake duct.
• Spray the MAF sensor with the cleaner and let it dry completely before reinstallation.

4. Test and Adjust Fuel System

• Tools Required: Fuel pressure gauge
• Attach the fuel pressure gauge to the fuel rail.
• Turn the ignition to the "on" position without starting the engine and check the pressure; it should meet manufacturer specifications (typically 30-50 psi for F-150).
• If pressure is low, check the fuel pump and fuel filter for issues and replace them as necessary.

5. Inspect Fuel Injectors

• Tools Required: Fuel injector cleaning kit or ultrasonic cleaner
• Remove the fuel injectors and inspect them for clogs or damage.
• Clean the injectors using a cleaning kit or replace them if they are defective.

6. Check for Vacuum Leaks

• Tools Required: Smoke machine or carburetor cleaner
• Use a smoke machine to introduce smoke into the intake system to identify leaks.
• Alternatively, spray carburetor cleaner around the intake manifold and listen for changes in engine RPM to locate leaks.
• Repair or replace any damaged hoses or gaskets.