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

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool down before starting repairs.

2. Inspect and Replace Air Intake Components

• Inspect Hoses and Clamps:
  • Visually check all hoses and clamps around the air intake for cracks or disconnections.
  • Replace any damaged hoses or clamps.
• Clean MAF Sensor:
  • Remove the MAF sensor from the intake.
  • Use MAF sensor cleaner to clean the sensor; do not touch the sensor elements.
  • Reinstall the MAF sensor securely.

3. Check Fuel System

• Test Fuel Pressure:
  • Connect a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position without starting the engine and check the pressure (should match manufacturer specifications).
  • If pressure is low, inspect the fuel pump and filter.
• Inspect Fuel Injectors:
  • Remove the fuel rail to access injectors.
  • Clean or replace clogged fuel injectors as necessary.

4. Inspect Vacuum Lines

• Visual Inspection:
  • Look for any disconnected or damaged vacuum lines.
  • Replace any faulty vacuum lines to ensure proper engine vacuum.

5. Test Oxygen Sensors

• Check Sensor Operation:
  • Use a multimeter to test the voltage output of the oxygen sensors.
  • Replace any faulty oxygen sensors that do not meet specifications.