how to fix P0171 code in Volkswagen Golf MK7.5 (2020-Present)

Solution

1. Preparation

• Gather tools such as an OBD-II scanner, multimeter, socket set, and cleaning supplies.
• Ensure the vehicle is parked on a flat surface, and the engine is off and cool.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect all air intake hoses and connections for cracks or disconnections.
  2. Tighten any loose clamps and replace damaged hoses.
  3. Use a smoke machine to detect any hidden vacuum leaks.
• Tools Required: Smoke machine, screwdriver set.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Disconnect the electrical connector from the MAF sensor.
  2. Remove the sensor from the air intake duct using the appropriate socket.
  3. Clean the MAF sensor with MAF cleaner spray. Allow it to dry completely before reinstallation.
• Tools Required: MAF cleaner spray, socket set.

4. Test Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition to the ON position (do not start) and check the fuel pressure reading against specifications (usually around 50-60 psi for the Golf).
  3. If pressure is low, inspect the fuel pump and fuel filter, replacing as necessary.
• Tools Required: Fuel pressure gauge.

5. Inspect and Clean Fuel Injectors

• Sub-steps:
  1. Remove the fuel rail with injectors from the engine.
  2. Inspect each injector for signs of blockage or leaks.
  3. Clean injectors with an appropriate cleaning solution or replace them if they are faulty.
• Tools Required: Injector cleaning kit, socket set.

6. Clear Codes and Test Drive

• Sub-steps:
  1. Use the OBD-II scanner to clear the P0171 code.
  2. Perform a test drive to allow the ECM to monitor for any new codes.
• Tools Required: OBD-II scanner.