how to fix P0171 code in Volkswagen Golf Eighth Generation (2020-present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, basic hand tools, multimeter, fuel pressure gauge, cleaning supplies (throttle body cleaner, MAF cleaner).
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to identify leaks around the intake manifold and hoses.
  3. Replace any damaged hoses or gaskets as necessary.

3. Clean the MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor, typically found between the air filter and throttle body.
  2. Disconnect the electrical connector and remove the MAF sensor.
  3. Spray MAF cleaner onto the sensor elements; do not touch them with fingers or tools.
  4. Allow the sensor to air dry completely before reinstallation.

4. Check Fuel Delivery

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Turn the ignition to the "ON" position without starting the engine to check for fuel pressure. Compare the reading to manufacturer specifications (typically around 50-60 psi for many vehicles).
  3. If pressure is low, inspect the fuel pump and fuel filter for blockages or failure and replace if necessary.

5. Inspect and Clean Fuel Injectors

• Sub-steps:
  1. Remove the fuel injector connectors and fuel rail (ensure fuel pressure is released first).
  2. Inspect the injectors for any signs of clogging or damage.
  3. Clean the injectors with an injector cleaning kit or replace them if they are defective.