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

Solution

1. Preparation

• Gather tools and parts needed for repair.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamps, rubber hoses.
• Inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
• Replace any damaged hoses.
• Tighten any loose clamps.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, torx screwdriver or socket.
• Remove the MAF sensor from the intake tube.
• Clean the sensor using MAF cleaner. Do not touch the sensor element.
• If the sensor is damaged, replace it with a new one.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge, appropriate fittings.
• Connect the fuel pressure gauge to the fuel rail test port.
• Turn the ignition to the "ON" position without starting the engine to check the pressure.
• Compare the reading to the manufacturer’s specifications. If low, inspect the fuel pump and filter for issues.

5. Inspect Fuel Injectors

• Tools Required: Fuel injector cleaning kit, multimeter.
• Remove the fuel rail with the injectors attached.
• Inspect injectors for clogs; clean with an injector cleaning kit if necessary.
• Test injectors with a multimeter to ensure they are receiving the correct voltage and firing properly.

6. Replace Oxygen Sensors (if necessary)

• Tools Required: O2 sensor socket, wrench.
• Locate the bank 1 O2 sensor (upstream) and remove it using the O2 sensor socket.
• Install a new O2 sensor and tighten to the specified torque value (typically 30 ft-lbs).
• Reconnect the battery.