how to fix the P0171 code in my BMW 5 Series G30/G31 (2017-2024)?

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure you have a clean workspace and wear safety gloves and goggles.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Repair Air Intake System

• Tools Required: Screwdriver set, vacuum gauge, intake manifold gasket
• Inspect all vacuum hoses connected to the air intake system for cracks or disconnections. Replace any damaged hoses.
• Check the intake manifold gasket for signs of wear or leaks; replace it if necessary.

3. Check and Clean MAF Sensor

• Tools Required: MAF sensor cleaner, Torx screwdriver
• Remove the MAF sensor from the air intake duct.
• Spray MAF sensor cleaner on the sensor elements to remove dirt and debris. Allow it to dry completely before reinstallation.
• Reinstall the MAF sensor, ensuring it is secured tightly.

4. Test Fuel Pressure

• Tools Required: Fuel pressure gauge
• Connect the fuel pressure gauge to the fuel rail test port.
• Turn the ignition to the ON position (do not start the engine) and read the fuel pressure. Compare with manufacturer specifications.
• If pressure is low, check the fuel pump and fuel filter for issues.

5. Inspect and Test Fuel Injectors

• Tools Required: Multimeter, injector cleaning kit
• Disconnect the fuel injector connectors and use a multimeter to check for proper voltage.
• If injectors are clogged, use an injector cleaning kit to clean them or replace them if they are faulty.

6. Clear Codes and Test Drive

• Use the OBD-II scanner to clear the P0171 code from the ECM.
• Reconnect the negative battery terminal.
• Start the engine and perform a test drive to ensure the issue is resolved.