how to fix the P0171 code on my Volkswagen Golf Seventh Generation (2013-2020)

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, screwdrivers, fuel pressure gauge, vacuum gauge, cleaning supplies (throttle body cleaner, MAF cleaner).
• Safety Warnings: Disconnect the battery before starting work to avoid electrical shorts. Allow the engine to cool before inspecting components.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect all air intake hoses for cracks or loose connections. Replace any damaged hoses.
  2. Tighten any loose clamps securing the hoses.
  3. Remove the air filter and check for blockages; replace the air filter if dirty.

3. Clean the Mass Air Flow (MAF) Sensor

• Sub-steps:
  1. Disconnect the MAF sensor electrical connector.
  2. Remove the MAF sensor from the air intake tube.
  3. Use MAF cleaner to gently spray the sensor elements. Allow it to dry completely before reinstalling.

4. Check Fuel Pressure

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition to the ON position (do not start) and check the pressure reading; it should match the specification in the service manual.
  3. If pressure is low, inspect the fuel pump and fuel filter for issues.

5. Inspect Throttle Body

• Sub-steps:
  1. Remove the intake duct from the throttle body.
  2. Use throttle body cleaner and a soft cloth to remove carbon buildup.
  3. Ensure the throttle plate operates smoothly without sticking.

6. Vacuum Leak Inspection and Repair

• Sub-steps:
  1. Use a vacuum gauge to check for leaks in the intake manifold.
  2. Inspect and replace any faulty gaskets or seals.
  3. If necessary, apply a smoke test to identify hidden vacuum leaks.