how to fix P0171 code in Volkswagen Golf Seventh Generation (2013-2020)

Solution

1. Preparation

• Gather tools and parts needed.
• Ensure the vehicle is on a flat surface and the engine is cool.
• Disconnect the battery to prevent electrical issues during the repair.

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 propane torch to identify any leaks.
  3. Replace any damaged hoses or fittings.
• Tools Required: Smoke machine or propane torch, pliers.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor, usually between the air filter and throttle body.
  2. Disconnect the electrical connector and remove the sensor.
  3. Use MAF cleaner spray to clean the sensing element (do not touch it).
  4. Reinstall the sensor and reconnect the electrical connector.
• Tools Required: MAF cleaner spray, screwdriver set.

4. Test and Replace Fuel Components if Necessary

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail to measure fuel pressure during cranking and idle.
  2. If pressure is below specifications (consult repair manual for correct values), check the fuel filter and pump.
  3. Replace the fuel filter if clogged; if pump is faulty, replace the fuel pump assembly.
• Tools Required: Fuel pressure gauge, socket set.

5. Inspect and Clean Fuel Injectors

• Sub-steps:
  1. Remove the fuel rail to access the injectors.
  2. Check for any visible blockages or dirt on the injectors.
  3. Clean injectors using an ultrasonic cleaner or replace them if they are malfunctioning.
• Tools Required: Socket set, ultrasonic cleaner (optional).

6. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use an OBD-II scanner to clear the P0171 code and any related codes.