my BMW X3 G01 (2018-2024) shows P0171 code, what does it mean?

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to ensure safety during the repair process.
• Allow the engine to cool if previously running.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect all air intake hoses for cracks or disconnections.
  2. Replace any damaged hoses or clamps as necessary.
  3. Ensure the air filter is clean and properly seated; replace if dirty.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Disconnect the MAF sensor electrical connector.
  2. Remove the MAF sensor from the air intake duct using a Torx screwdriver.
  3. Clean the sensor with MAF cleaner spray and allow it to dry.
  4. Reinstall the sensor and reconnect the electrical connector.

4. Inspect Fuel System

• Sub-steps:
  1. Use a fuel pressure gauge to check the fuel pressure at the fuel rail.
  2. If pressure is low, inspect the fuel pump and replace if necessary.
  3. Check and replace the fuel filter if it hasn't been changed in accordance with the maintenance schedule.

5. Examine Oxygen Sensors

• Sub-steps:
  1. Using a multimeter, test the voltage output of the upstream oxygen sensor.
  2. If the sensor is faulty, remove it with an oxygen sensor socket and replace it with a new one.
  3. Clear the error codes using the OBD-II scanner after repairs.