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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal.
• Ensure the engine is cool before beginning work.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect the air intake hoses and connections for any signs of damage or disconnection.
  2. Replace any damaged hoses or clamps as necessary.
  3. Clean the MAF sensor using MAF cleaner, taking care not to touch the sensor element.

3. Test and Replace Fuel System Components

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail and turn the ignition to the "on" position without starting the engine.
  2. Check if the fuel pressure is within specifications (usually around 50-60 psi for VW models).
  3. If pressure is low, inspect the fuel pump, fuel filter, and fuel injectors.
  4. Replace any failing components; if injectors are faulty, use a suitable injector cleaning kit or replace them.

4. Check Vacuum Lines

• Sub-steps:
  1. Inspect all vacuum lines connected to the intake manifold for cracks or leaks.
  2. Replace any damaged vacuum lines, ensuring secure connections.

5. Clear Codes and Test Drive

• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0171 code and any other stored codes.
  3. Start the engine and perform a test drive to monitor engine performance.