how to fix P0171 code in Volkswagen Golf MK7 (2015-2019)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle's battery to ensure safety.
• Raise the vehicle using a jack and support it with jack stands if needed.

2. Inspect and Repair Air Intake System

• Tools Required: Screwdriver, hose clamp pliers, flashlight
• Sub-steps:
  1. Visually inspect all air intake hoses for cracks or disconnections.
  2. Tighten or replace any loose or damaged clamps and hoses.
  3. Clean the air filter and replace it if dirty.

3. Service the Mass Air Flow Sensor

• Tools Required: MAF cleaner, soft cloth
• Sub-steps:
  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the electrical connector and remove the sensor.
  3. Clean the sensor gently with MAF cleaner and a soft cloth.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

4. Check Fuel System

• Tools Required: Fuel pressure gauge
• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail service port.
  2. Turn the ignition on (do not start the engine) and check the pressure reading.
  3. If the pressure is below the specification (usually around 50-60 psi), inspect the fuel pump and fuel filter for issues.
  4. Replace the fuel filter if necessary.

5. Inspect Fuel Injectors

• Tools Required: Injector cleaner, multimeter
• Sub-steps:
  1. Remove the fuel injectors from the fuel rail.
  2. Clean the injectors using an appropriate injector cleaning solution.
  3. Use a multimeter to test each injector's resistance; replace any that are outside of the specified range.
  4. Reinstall the injectors and fuel rail.

6. Clear Codes and Test Drive

• Tools Required: OBD-II scanner
• Sub-steps:
  1. Reconnect the vehicle's battery.
  2. Use the OBD-II scanner to clear the P0171 code.
  3. Take the vehicle for a test drive to ensure the code does not reappear.