how to fix P0171 code in Skoda Octavia NFL (2020-Present)

Learn how to diagnose and fix P0171 engine lean condition in Skoda Octavia NFL. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts required for repairs.
• Disconnect the negative terminal of the battery to prevent electrical shorts.

2. Inspect and Repair Vacuum Leaks

• Visually inspect all vacuum hoses connected to the intake manifold.
• Use a smoke machine or carburetor cleaner to identify leaks.
• Replace any damaged hoses or gaskets found during the inspection.

3. Clean or Replace the MAF Sensor

• Disconnect the wiring harness from the MAF sensor.
• Remove the MAF sensor from the air intake duct using a Torx screwdriver.
• Clean the sensor with MAF cleaner spray; do not touch the sensor element.
• If it’s heavily contaminated or damaged, replace it with a new one.
• Reinstall the MAF sensor, reconnect the wiring harness, and ensure it is secured.

4. Check and Adjust Fuel Pressure

• Connect a fuel pressure gauge to the fuel rail test port.
• Start the engine and verify that the fuel pressure matches manufacturer specifications (usually around 50-60 psi).
• If pressure is low, check the fuel pump and fuel filter; replace if necessary.

5. Inspect Fuel Injectors

• Using a multimeter, check the resistance of each fuel injector.
• If any injector shows an open circuit or is out of spec, replace the injector.
• Clean injectors using a professional cleaning kit or replace them if they are clogged beyond cleaning.

6. Evaluate Oxygen Sensors

• Check the upstream oxygen sensor’s voltage output with a multimeter while the engine is running.
• If the readings are erratic or out of the normal range, replace the oxygen sensor.