how to fix P0171 code on Ford F-150 13th Generation (2015-2020)

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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety during work.
• Tools Required: OBD-II scanner, socket set, fuel pressure gauge, multimeter, vacuum gauge.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  • Use a smoke machine or carburetor cleaner to identify leaks: apply around suspected areas and watch for changes in engine RPM.
  • Replace any damaged hoses or gaskets found during inspection.

3. Clean MAF Sensor

• Sub-steps:
  • Locate the MAF sensor in the air intake duct.
  • Remove the sensor using a socket set, being careful not to damage it.
  • Spray MAF cleaner on the sensor element and allow it to dry completely.
  • Reinstall the MAF sensor and secure it properly.

4. Test and Repair Fuel System

• Sub-steps:
  • Connect the fuel pressure gauge to the fuel rail.
  • Turn the ignition on (without starting the engine) to check for fuel pressure; it should meet manufacturer specifications (typically around 50-60 psi).
  • If pressure is low, inspect the fuel pump and filter for issues.
  • If injectors are suspect, remove them and clean or replace as necessary.

5. Reconnect Battery and Clear Codes

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