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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery negative terminal to prevent electrical shorts.

2. Inspect and Repair Air Intake System

• Tools Required: Socket set, pliers
• Sub-steps:
  1. Visually inspect the air intake hoses and connections for cracks or loose fittings.
  2. Replace any damaged hoses using a socket set to remove clamps.
  3. Reconnect all fittings securely.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, screwdriver
• Sub-steps:
  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the electrical connector and remove the MAF sensor using a screwdriver.
  3. Clean the sensor using MAF cleaner and allow it to dry, or replace it if damaged.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

4. Check Fuel System

• Tools Required: Fuel pressure gauge, socket set
• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition key to the "On" position (do not start) to check the fuel pressure.
  3. Compare the reading with the manufacturer specifications; replace the fuel pump if pressure is low.
  4. Inspect the fuel injectors for clogs by using a cleaning kit; clean or replace as necessary.

5. Inspect Vacuum Lines

• Tools Required: Visual inspection
• Sub-steps:
  1. Trace all vacuum lines from the intake manifold.
  2. Look for any signs of wear, cracks, or disconnections.
  3. Replace or reattach any damaged or disconnected lines.

6. Test and Reconnect Battery

• Reconnect the battery negative terminal.
• Start the engine and let it idle for a few minutes to stabilize.