why does my BMW X3 G01 (2018-2024) display a check engine light with P0174

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety while working on the vehicle.
• Allow the engine to cool down before starting work.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum lines for cracks or disconnections.
  • Use a smoke machine to detect leaks in the intake system.
  • Replace any damaged hoses or components.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner spray, screwdriver, torque wrench
• Sub-steps:
  • Locate the MAF sensor, usually found between the air filter and the throttle body.
  • Disconnect the electrical connector and remove the sensor using a screwdriver.
  • Clean the MAF sensor with a dedicated MAF cleaner. Allow it to dry completely.
  • If the sensor is faulty, replace it with a new one, ensuring to torque it to the manufacturer’s specifications.

4. Inspect and Test Fuel System

• Tools Required: Fuel pressure gauge
• Sub-steps:
  • Connect the fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position (do not start the engine) and record the pressure reading.
  • Compare the reading to the manufacturer’s specifications. If pressure is low, inspect the fuel pump and filter for clogs or failures.

5. Inspect Fuel Injectors

• Sub-steps:
  • Remove the engine cover and the fuel rail to access the injectors.
  • Inspect each injector for signs of clogging or leakage.
  • Clean the injectors using a fuel injector cleaning kit or replace them if necessary.