how to fix P0171 code on my Volkswagen Golf MK7.5 (2020-Present)?

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, vacuum gauge, fuel pressure gauge, MAF cleaner, safety goggles, gloves.
• Disconnect the battery to ensure safety while working on the vehicle.

2. Inspect and Repair Air Intake System

• Inspect for Leaks:
  • Visually inspect air intake hoses and gaskets for cracks or loose connections.
  • Use a smoke machine to detect leaks in the intake system if necessary.
• Repair or Replace:
  • Replace any damaged hoses or gaskets found during inspection.

3. Clean or Replace MAF Sensor

• Cleaning the MAF Sensor:
  • Remove the MAF sensor from the air intake duct.
  • Spray MAF cleaner onto the sensor elements (do not touch them).
  • Allow it to dry completely before reinstalling.
• Replacement (if cleaning is ineffective):
  • Disconnect the electrical connector and remove the MAF sensor.
  • Install a new MAF sensor and reconnect the electrical connector.

4. Check Fuel Pressure

• Testing:
  • Attach a fuel pressure gauge to the fuel rail service port.
  • Turn the ignition to the ON position (do not start the engine) and check the pressure reading.
• Adjustment:
  • If the pressure is below specifications, inspect the fuel pump and fuel filter for issues. Replace as necessary.

5. Inspect Fuel Injectors

• Visual Inspection:
  • Remove the injector rail and visually inspect each injector for signs of clogging or leaks.
• Testing:
  • Use a multimeter to check injector resistance; replace any that are outside the specified range.
  • Clean or replace clogged injectors as necessary.