my BMW X5 F15 (2014-2019) has a P0171 code, how do I fix it

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the vehicle is parked on a level surface.
• Disconnect the battery negative terminal to prevent electrical shorts.

2. Inspect and Repair Air Intake System

• Tools Required: Screwdriver set, hose clamps, vacuum gauge
• Inspect all air intake hoses for cracks or loose connections.
  • Tighten or replace any faulty hoses.
• Check the air filter.
  • If dirty, replace it with a new one.

3. Check and Clean MAF Sensor

• Tools Required: MAF sensor cleaner
• Remove the MAF sensor from the intake duct.
  • Be cautious not to touch the sensor elements.
• Spray the MAF sensor cleaner on the sensor and allow it to dry completely before reinstalling.

4. Test and Repair Fuel System

• Tools Required: Fuel pressure gauge
• Connect the fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position (do not start) and check the fuel pressure.
  • If the pressure is below specifications, check the fuel pump and filter for issues.
• If fuel pressure is adequate, inspect the fuel injectors.
  • Clean or replace any clogged injectors.

5. Clear Codes and Test Drive

• Reconnect the battery terminal.
• Use the OBD-II scanner to clear the P0171 code.
• Start the engine and let it idle for a few minutes, then perform a test drive to verify that the code does not return.