how to fix P0174 code in BMW 5 Series G30/G31 (2017-2024)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on the electrical systems.
• Allow the engine to cool before commencing work.

2. Inspect and Repair Air Intake System

• Tools Required: Screwdriver set, vacuum gauge, torque wrench.
• Sub-steps:
  1. Visually inspect the air intake hoses and connections for any signs of wear or damage.
  2. Tighten any loose clamps or fittings.
  3. Replace any damaged hoses or gaskets.
  4. If necessary, remove the intake manifold to inspect for internal leaks.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, Torx screwdriver.
• Sub-steps:
  1. Locate the MAF sensor on the air intake duct.
  2. Disconnect the electrical connector and unscrew the MAF sensor from its housing.
  3. Use MAF sensor cleaner to clean the sensor element carefully.
  4. Allow it to dry completely before reinstalling it. If damaged, replace the MAF sensor.

4. Test and Adjust Fuel Pressure

• Tools Required: Fuel pressure gauge, fuel line disconnect tool.
• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail.
  2. Turn the ignition to the ON position (do not start) and check the pressure reading.
  3. Compare the reading to BMW specifications; if it's low, inspect the fuel pump and filter for issues.
  4. Replace any faulty components as needed.

5. Check and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, smoke machine (optional).
• Sub-steps:
  1. Attach a vacuum gauge to a suitable vacuum port.
  2. Start the engine and observe the vacuum reading—low readings may indicate a leak.
  3. If available, use a smoke machine to identify hard-to-find leaks.
  4. Repair or replace any faulty vacuum lines.