how to troubleshoot a P0171 code in my Ford F-150 Fourteenth Generation (2021-present)

Learn how to troubleshoot and fix P0171 engine lean condition in Ford F-150 (2021-present). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool down before working on it.

2. Inspect and Repair Air Intake System

• Sub-steps:
  • Visually inspect the vacuum hoses and intake manifold for cracks or disconnections.
  • Tighten any loose clamps and replace any damaged hoses.
  • Check the air filter; replace if dirty.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner spray, screwdriver
• Sub-steps:
  • Locate the MAF sensor on the air intake duct.
  • Disconnect the electrical connector.
  • Remove the sensor using a screwdriver.
  • Spray MAF cleaner on the sensor elements and allow to dry; do not touch them.
  • Reinstall the sensor and reconnect the electrical connector.

4. Check and Repair Fuel System

• Tools Required: Fuel pressure gauge
• Sub-steps:
  • Connect the fuel pressure gauge to the Schrader valve on the fuel rail.
  • Turn the ignition to the "ON" position without starting the engine and check the pressure readings against manufacturer specifications.
  • If pressure is low, inspect the fuel pump, filter, and relay for issues. Replace any faulty components.

5. Inspect Fuel Injectors

• Tools Required: Injector cleaner kit, multimeter
• Sub-steps:
  • Remove the fuel injectors from the fuel rail.
  • Clean the injectors using an injector cleaning kit or replace them if they are clogged or damaged.
  • Reinstall the injectors and ensure all connections are secure.

6. Test Oxygen Sensor

• Tools Required: Multimeter
• Sub-steps:
  • Locate the oxygen sensor on Bank 1.
  • Disconnect the sensor and check the voltage output with a multimeter.
  • If the voltage is outside the acceptable range, replace the oxygen sensor.