my Volkswagen Golf MK7.5 (2020-Present) has a check engine light for P0171, what does this mean?

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to avoid electrical shorts.
• Allow the engine to cool before starting work.

2. Inspect and Repair Air Intake System

• Tools Required: Socket set, screwdrivers
• Remove the engine cover, if applicable.
• Inspect the air intake duct for any cracks or loose fittings; replace or tighten as necessary.
• Check the air filter; replace if dirty or clogged.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner or electronic cleaner
• Locate the MAF sensor in the air intake system.
• Disconnect the electrical connector and remove the sensor.
• Clean the sensor with MAF cleaner; do not touch the sensor element.
• Reinstall the MAF sensor and securely reconnect the electrical connector.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge
• Locate the fuel rail and connect the fuel pressure gauge.
• Turn the ignition to the "on" position (do not start) and observe the gauge reading.
• If the pressure is below specifications, check the fuel pump and filter for issues.

5. Inspect Vacuum Hoses

• Tools Required: Visual inspection tools
• Follow the vacuum lines from the intake manifold to various engine components.
• Look for cracks, wear, or loose connections and replace any damaged hoses.

6. Test Fuel Injectors

• Tools Required: Multimeter, fuel injector cleaner
• Disconnect each fuel injector connector.
• Use a multimeter to check for proper resistance based on specifications.
• If faulty, replace the injector; if they are dirty, clean with an injector cleaner.