how to fix P0174 code in BMW 5 Series F10/F11 (2010-2017)

Solution

1. Preparation

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

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses connected to the intake manifold and throttle body for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to identify any vacuum leaks around the intake manifold and gaskets.
  3. Replace any damaged hoses or gaskets as necessary.

3. Clean or Replace MAF Sensor

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

4. Check and Adjust Fuel Pressure

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Turn the ignition key to the "On" position (do not start) and check the fuel pressure; it should be within manufacturer specifications.
  3. If the pressure is low, inspect the fuel pump and fuel filter for blockages or failures, and replace as necessary.

5. Inspect Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on bank two.
  2. Use a multimeter to test the sensors for proper voltage output and response to engine changes.
  3. Replace any faulty oxygen sensors.