what are common causes for P0171 code in Ford F-150 13th Generation (2015-2020)

Learn how to diagnose and fix P0171 engine lean condition in Ford F-150 (2015-2020). Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts for the repair.
• Ensure the vehicle is parked on a level surface with the engine off and cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses and connections for cracks or disconnections.
  • Use a smoke machine or carburetor cleaner to identify leaks in the intake manifold or associated components.
  • Replace any damaged hoses or gaskets as necessary.

3. Clean or Replace the MAF Sensor

• Sub-steps:
  • Locate the MAF sensor in the air intake duct.
  • Remove the MAF sensor using a suitable socket set.
  • Clean the sensor using MAF cleaner spray and a soft cloth (do not touch the sensor element).
  • If damage is found, replace the MAF sensor with a new one.

4. Check Fuel Delivery

• Sub-steps:
  • Connect a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "on" position without starting the engine and check the fuel pressure.
  • If the pressure is below specifications (consult service manual for correct pressure range), inspect and replace the fuel filter or fuel pump as necessary.

5. Inspect and Test Oxygen Sensor

• Sub-steps:
  • Locate the oxygen sensor in the exhaust system upstream of the catalytic converter.
  • Use a multimeter to test the voltage output of the sensor while the engine is running.
  • If the readings are not within manufacturer specifications, replace the oxygen sensor.