how to fix P0171 code in BMW 5 Series F10/F11 (2010-2017)

Solution

1. Preparation

• Gather required tools and parts.
• Disconnect the battery to ensure safety before working on electrical components.

2. Inspect and Repair Air Intake

• Tools Required: Screwdriver set, hose clamps, flashlight
• Check all intake hoses for cracks or loose connections.
• Tighten or replace any faulty hoses as necessary.
• Inspect the intake manifold gaskets and replace them if they show signs of wear or damage.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner (specific cleaner for MAF sensors), screwdriver
• Disconnect the MAF sensor electrical connector.
• Remove the MAF sensor from the air intake duct.
• Spray the MAF sensor with the dedicated MAF cleaner and allow it to dry completely.
• Reinstall the MAF sensor, ensuring it is securely connected.

4. Check 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 the engine) to check if the fuel pressure meets specifications (typically between 50-60 psi for BMW).
• If pressure is low, inspect the fuel pump and filter for issues; replace as necessary.

5. Inspect Fuel Injectors

• Tools Required: Injector cleaner kit (if cleaning), replacement injectors if needed
• Remove the fuel rail and inspect the injectors for clogs or leaks.
• Clean injectors with a cleaning kit or replace them if they are damaged or clogged.

6. Check for Vacuum Leaks

• Tools Required: Smoke machine (optional), hose clamps
• Perform a smoke test to check for vacuum leaks in the engine's intake system.
• Repair any identified leaks by replacing damaged hoses or gaskets.