how to fix P0171 code in Ford F-150 12th Generation (2009-2014)

Learn how to diagnose and fix P0171 engine lean condition in Ford F-150 (2009-2014). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather all tools and parts required for repair.
• Disconnect the vehicle battery to ensure safety.
• Ensure the engine is cool before starting work.

2. Inspect and Clean the MAF Sensor

• Remove the MAF sensor from the air intake duct.
• Use MAF sensor cleaner to spray and clean the sensing elements.
• Allow the sensor to dry completely before reinstallation.

3. Check for Vacuum Leaks

• Inspect all vacuum hoses visually for cracks or disconnections.
• Apply a smoke test or use carburetor cleaner around suspected leak areas while the engine is running.
• Repair or replace any damaged hoses or components.

4. Measure Fuel Pressure

• Connect a fuel pressure gauge to the fuel rail test port.
• Turn the ignition to the "ON" position without starting the engine and check the pressure reading.
• Compare the reading to the manufacturer's specifications (typically around 30-50 psi for F-150).
• If the pressure is low, check the fuel pump and filter for issues.

5. Inspect Fuel Injectors

• Remove the fuel rail to access the injectors.
• Check for clogs by visually inspecting and cleaning the injectors if necessary.
• Consider replacing injectors if they are faulty or not functioning properly.

6. Reconnect and Reset

• Reconnect the battery and clear the P0171 code using the OBD-II scanner.
• Start the engine and observe for any reoccurrence of the code.