how to fix P0174 code in Volkswagen Golf Eighth Generation (2020-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the engine is cool before starting work.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses for cracks, breaks, or loose connections.
  • Use a smoke machine or carburetor cleaner to detect leaks around the intake manifold and vacuum lines.
  • Replace any damaged hoses or gaskets found during inspection.

3. Clean or Replace MAF Sensor

• Sub-steps:
  • Locate the MAF sensor on the air intake duct.
  • Disconnect the electrical connector and remove the sensor using a Torx screwdriver.
  • Clean the sensor with MAF cleaner spray (do not use other cleaners).
  • If the sensor is damaged or cleaning does not resolve the issue, replace it with a new one.
  • Reinstall the sensor and reconnect the electrical connector.

4. Check and Repair Fuel System

• Sub-steps:
  • Connect a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position (do not start) and check the pressure reading against manufacturer specifications.
  • If pressure is low, check the fuel pump, filter, and relay for issues.
  • Inspect fuel injectors for clogs and replace if necessary.

5. Test and Replace Engine Coolant Temperature Sensor (if needed)

• Sub-steps:
  • Locate the engine coolant temperature sensor.
  • Disconnect the sensor and use a multimeter to check its resistance against specifications at various temperatures.
  • If out of specifications, replace the sensor with a new one.