how to fix P0174 code in Volkswagen Golf MK7 (2015-2019)

Solution

1. Preparation

• Gather tools: OBD-II scanner, vacuum gauge, fuel pressure gauge, MAF cleaner, socket set, torque wrench, and screwdrivers.
• Disconnect the negative battery terminal to ensure safety while working on electrical components.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Start the engine and listen for hissing sounds, which may indicate a vacuum leak.
  2. Use a smoke machine or carb cleaner to identify leaks around vacuum hoses and intake manifold.
  3. Replace any damaged hoses or gaskets found during the inspection.
• Tools Required: Smoke machine or carb cleaner.

3. Check and Clean MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the electrical connector and remove the MAF sensor from its housing.
  3. Spray MAF cleaner onto the sensor element; do not touch it with your hands.
  4. Reinstall the MAF sensor and reconnect the electrical connector.
• Tools Required: MAF cleaner.

4. Test Fuel Pressure

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading.
  3. Compare the reading to the manufacturer's specifications; if low, check for fuel pump issues or clogged fuel filter.
  4. Replace the fuel pump or filter if necessary.
• Tools Required: Fuel pressure gauge.

5. Inspect Fuel Injectors

• Sub-steps:
  1. Remove the engine cover to access the fuel rail and injectors.
  2. Check for fuel leaks around the injectors and their seals.
  3. If necessary, remove and clean the injectors using a dedicated injector cleaner or replace them if they are clogged.
• Tools Required: Socket set, injector cleaning kit.