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

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down before beginning work.

2. Inspect and Clean the MAF Sensor

• Tools Required: MAF cleaner, screwdriver, torque wrench.
• Remove the MAF sensor by unscrewing the retaining screws.
• Spray the MAF cleaner on the sensor elements and allow it to dry completely before reinstallation.
• Reinstall the MAF sensor and torque to manufacturer specifications.

3. Check for Vacuum Leaks

• Tools Required: Smoke machine or carburetor cleaner.
• Start the engine and use the smoke machine to introduce smoke into the intake system; look for leaks.
• If using carburetor cleaner, lightly spray around vacuum hoses and the intake manifold; listen for changes in engine RPM to identify leaks.
• Repair or replace any damaged hoses or gaskets found.

4. Test Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Connect the fuel pressure gauge to the fuel rail.
• Turn the ignition on to prime the fuel system, then check the pressure reading.
• Compare the reading to the manufacturer’s specifications; if low, check the fuel pump and filter.

5. Inspect Fuel Injectors

• Tools Required: Multimeter, injector cleaner.
• Disconnect the fuel injectors and check resistance with a multimeter; compare to manufacturer specs.
• Clean the injectors using a fuel injector cleaning kit if they are clogged.
• Reconnect injectors and ensure proper seating.

6. Examine the Oxygen Sensor

• Tools Required: O2 sensor socket, multimeter.
• Disconnect the oxygen sensor and test its voltage output with a multimeter while the engine is running.
• Replace the sensor if readings are outside of normal operating range.