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

Solution

1. Preparation

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

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamps
• Visually inspect all vacuum hoses connected to the intake manifold for cracks or loose connections.
• Use a vacuum gauge to test for leaks; repair or replace any defective hoses or gaskets.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner
• Remove the MAF sensor from its housing.
• Spray the MAF sensor with MAF cleaner, avoiding contact with the sensor elements.
• Allow it to dry completely before reinstalling the sensor.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge
• Locate the fuel rail and attach the fuel pressure gauge.
• Turn the ignition to the "On" position without starting the engine and check the pressure; it should match manufacturer specifications.
• If pressure is low, inspect the fuel pump and fuel filter for blockages or failures.

5. Inspect Oxygen Sensors

• Tools Required: O2 sensor socket
• Locate the upstream oxygen sensor and use the O2 sensor socket to disconnect it.
• Test the sensor with a multimeter or scan tool to check for proper voltage output.
• Replace the sensor if it is not functioning correctly.

6. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use the OBD-II scanner to clear the P0171 code and any other related codes.