how to fix the P0174 code on my Volkswagen Golf MK7 (2015-2019)?

Solution

1. Preparation

• Gather tools: OBD-II scanner, fuel pressure gauge, multimeter, socket set, torque wrench, vacuum gauge, cleaning supplies.
• Disconnect the negative battery terminal to prevent any electrical shorts.
• Allow the engine to cool before starting work.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum lines for cracks or disconnections.
  • Use a vacuum gauge to check for pressure in the intake manifold.
  • Replace any damaged hoses and reseal gaskets as necessary.

3. Check and Clean MAF Sensor

• Sub-steps:
  • Locate the MAF sensor in the intake system (usually between the air filter and throttle body).
  • Remove the sensor gently using a socket set, being careful not to damage the wiring.
  • Clean the sensor with MAF cleaner spray and let it dry.
  • Reinstall the sensor and ensure it is secured properly.

4. Test and Replace Fuel Pressure Regulator (if necessary)

• Sub-steps:
  • Connect the fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading.
  • If the pressure is below specifications, locate the fuel pressure regulator and replace it.
  • Reconnect all components and ensure no leaks are present.

5. Inspect and Test Fuel Injectors

• Sub-steps:
  • Disconnect the fuel injector connectors.
  • Use a multimeter to check the resistance of each injector; it should be within manufacturer specifications.
  • If any injector is out of spec, replace it.