how to fix P0171 lean condition code on BMW X5 F15 (2014-2019)

Solution

1. Preparation

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

2. Inspect and Repair Air Intake System

• Inspect MAF Sensor:

  1. Remove the intake duct connected to the MAF sensor.
  2. Clean the MAF sensor using MAF cleaner spray (do not touch the sensor element).
  3. Reinstall the intake duct securely.

• Check for Intake Leaks:

  1. Visually inspect all intake hoses and connections for cracks or loose fittings.
  2. If leaks are found, replace the damaged hoses or secure loose connections.

3. Check Fuel System

• Fuel Pressure Test:

  1. Attach a fuel pressure gauge to the fuel rail Schrader valve.
  2. Turn the ignition key to the ON position (do not start) and check the fuel pressure.
  3. Compare the pressure reading with manufacturer specifications (typically 50-60 psi for BMW).
  4. If pressure is low, inspect the fuel pump and fuel filter for replacement.

• Inspect Fuel Injectors:

  1. Remove the fuel rail and inspect the injectors for clogs or leaks.
  2. Clean or replace any faulty injectors.

4. Inspect Vacuum Lines and Throttle Body

• Vacuum Line Inspection:

  1. Trace all vacuum hoses and connections to the intake manifold.
  2. Replace any cracked or disconnected vacuum lines.

• Throttle Body Cleaning:

  1. Remove the throttle body from the intake manifold.
  2. Clean the throttle body with throttle body cleaner and a soft cloth.
  3. Reinstall the throttle body using new gaskets if necessary.

5. Reassemble and Clear Codes

• Reconnect all components and hoses removed during the repair.
• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0171 code from the ECM.