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 tools and parts needed for the repair.
• Disconnect the negative battery terminal to prevent electrical issues.
• Allow the engine to cool if it has been running.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamps, and a socket set.
• Steps:
  1. Use a vacuum gauge to check for proper vacuum readings.
  2. Visually inspect all vacuum hoses for cracks or disconnections.
  3. If leaks are found, replace damaged hoses or reattach loose connections.
  4. Inspect the intake manifold gasket for leaks and replace if necessary.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner and a screwdriver.
• Steps:
  1. Locate the MAF sensor, typically found between the air filter and throttle body.
  2. Disconnect the electrical connector and remove the MAF sensor from the air intake.
  3. Spray the MAF sensor with the cleaner and allow it to dry completely.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Steps:
  1. Connect the fuel pressure gauge to the fuel rail's test port.
  2. Turn the ignition to the "ON" position (do not start the engine) and check the fuel pressure reading.
  3. Compare the reading to the manufacturer’s specifications. If it's low, inspect the fuel pump and fuel filter for issues.
  4. If necessary, replace the fuel pump or filter.

5. Inspect and Clean Fuel Injectors

• Tools Required: Fuel injector cleaning kit or professional cleaning service.
• Steps:
  1. Remove the fuel injectors from the fuel rail.
  2. Clean the injectors using the cleaning kit or take them to a professional for cleaning.
  3. Reinstall the cleaned or new injectors ensuring proper sealing.

6. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0171 code and any other related codes.