my Volkswagen Golf MK7.5 (2020-Present) is using too much fuel what's wrong

Solution

1. Preparation

• Tools Required: OBD-II scanner, fuel pressure gauge, multimeter, socket set, torque wrench.
• Gather necessary parts if replacements are needed (e.g., air filter, fuel injectors, oxygen sensors).

2. Address Fault Codes

• Retrieve and document any error codes from the OBD-II scanner.
• Research the codes to determine specific components needing attention.
• Clear the codes after noting them to monitor if they return.

3. Replace Air Filter

• Open the hood and locate the air filter box.
• Remove the clips or screws securing the air filter cover.
• Take out the old air filter and inspect the housing for debris.
• Install a new air filter, ensuring it fits snugly.
• Reattach the filter cover and secure it.

4. Inspect and Clean Fuel Injectors

• Relieve fuel system pressure by removing the fuel pump fuse and running the engine until it stalls.
• Disconnect the fuel lines from the injectors using a socket set (ensure to collect any spilled fuel).
• Remove the injectors from the intake manifold.
• Clean the injectors with a dedicated cleaner or replace them if required.
• Reinstall the injectors and reconnect the fuel lines.

5. Test and Replace Oxygen Sensors

• Locate the upstream and downstream oxygen sensors.
• Disconnect the electrical connectors and use a multimeter to test their resistance.
• If out of spec, replace the sensors with new ones.
• Reconnect the electrical connectors securely.

6. Check Fuel Pressure

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position without starting the engine to check the pressure.
• Compare the reading to manufacturer specifications.
• If the pressure is too high or low, investigate the fuel pump and pressure regulator.