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

Solution

1. Preparation

• Gather tools and parts needed for repairs.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Socket set, flashlight.
• Instructions:
  1. Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to locate any leaks around the intake manifold and hoses.
  3. Replace any damaged hoses or gaskets as needed.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner, screwdrivers.
• Instructions:
  1. Disconnect the MAF sensor electrical connector and remove the sensor from the intake.
  2. Spray MAF cleaner onto the sensor elements and allow it to dry completely.
  3. Reinstall the MAF sensor and reconnect the electrical connector.

4. Check and Adjust Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Instructions:
  1. Attach the fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition key to the "ON" position (do not start the engine) and check the pressure.
  3. If the pressure is below specification, check the fuel pump and fuel filter for issues and replace as necessary.

5. Inspect Fuel Injectors

• Tools Required: Multimeter, ultrasonic cleaner (if applicable).
• Instructions:
  1. Disconnect the fuel injector electrical connectors.
  2. Use a multimeter to check the resistance of each injector.
  3. Clean injectors using an ultrasonic cleaner or replace if they are faulty.

6. Reinstall and Reset

• Instructions:
  1. Reconnect any components that were removed during the inspection.
  2. Reconnect the negative battery terminal.
  3. Clear the error codes using the OBD-II scanner.