how to fix P0174 code in Skoda Octavia NFL (2020-Present)

Learn how to diagnose and fix P0174 lean air-fuel mixture issue in Skoda Octavia NFL. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Tools Required: OBD-II scanner, MAF cleaner, vacuum gauge, fuel pressure gauge, socket set, screwdrivers.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool before working on it.

2. Clean the MAF Sensor

• Locate the MAF sensor in the intake tube.
• Disconnect the electrical connector and remove the sensor from the intake.
• Spray MAF cleaner onto the sensor elements. Do not touch the sensor with your fingers.
• Allow the sensor to dry completely before reinstallation.

3. Inspect for Vacuum Leaks

• With the engine running, use a vacuum gauge to check for proper vacuum levels.
• Spray a small amount of carburetor cleaner around the intake manifold and hoses while the engine is running. If the idle changes, there is a vacuum leak.
• Tighten or replace any loose or damaged hoses.

4. Check Fuel Pressure

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position but do not start the engine, and check the pressure reading against manufacturer specifications.
• If the pressure is low, inspect the fuel pump, filter, and lines for blockages or damage.

5. Inspect Fuel Injectors

• Remove the fuel injector connectors and test the injectors with a multimeter for proper resistance according to manufacturer specifications.
• If necessary, clean the injectors using an ultrasonic cleaner or replace them if they are faulty.

6. Reassemble and Test

• Reinstall all components removed during the procedure.
• Reconnect the battery.
• Clear the P0174 code using the OBD-II scanner and take the vehicle for a test drive to ensure the issue is resolved.