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

Solution

1. Preparation

• Gather tools and parts required for repairs.
• Ensure the vehicle is parked on a level surface with the engine turned off and cooled.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Repair Air Intake System

1. Check Air Filter:

   • Remove the air filter housing cover.
   • Inspect the air filter for dirt and debris; replace if necessary.

2. Inspect Hoses and Clamps:

   • Visually inspect all hoses connected to the intake for cracks or leaks.
   • Tighten or replace any loose or damaged clamps and hoses.

3. Clean or Replace MAF Sensor

1. Remove MAF Sensor:

   • Disconnect the electrical connector from the MAF sensor.
   • Unscrew and remove the MAF sensor from the air intake duct.

2. Clean MAF Sensor:

   • Use MAF sensor cleaner (do not use other cleaners) to spray the sensor elements.
   • Allow it to dry completely before reinstalling.

3. Reinstall MAF Sensor:

   • Secure the MAF sensor back to the air intake duct and reconnect the electrical connector.

4. Check and Adjust Fuel Pressure

1. Connect Fuel Pressure Gauge:

   • Locate the fuel rail and connect the fuel pressure gauge to the Schrader valve.

2. Test Fuel Pressure:

   • Turn the ignition to the "ON" position (do not start the engine) and read the pressure.
   • Compare the reading to manufacturer specifications; replace the fuel pump or filter if necessary.

5. Inspect for Vacuum Leaks

1. Perform a Smoke Test:
   • Connect a smoke machine to the intake manifold and introduce smoke to visually identify leaks.
   • Seal any leaks found during the inspection.

6. Check Fuel Injectors

1. Inspect Injectors:
   • Remove the fuel rail with injectors attached.
   • Check for clogged injectors and clean or replace as needed.