why does my Volkswagen Golf MK7 (2015-2019) engine light come on with code P0303?

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the battery to prevent electrical shocks.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket
• Remove the ignition coil cover if necessary.
• Disconnect the ignition coil connector from cylinder 3.
• Remove the ignition coil using a socket wrench.
• Remove the spark plug from cylinder 3 using a spark plug socket.
• Inspect the spark plug for signs of wear (e.g., carbon buildup, damage).
• If worn, replace it with a new spark plug, ensuring it’s gapped according to manufacturer specifications (typically 0.028-0.032 inches).
• Reinstall the ignition coil and reconnect the connector.

3. Check and Replace Fuel Injector (if necessary)

• Tools Required: Fuel injector removal tool, torque wrench
• Disconnect the fuel injector connector from cylinder 3.
• Remove the fuel rail if needed to access the injector.
• Carefully remove the fuel injector from cylinder 3.
• Inspect the injector for clogs or damage.
• Replace it with a new fuel injector if defective.
• Reinstall the fuel rail (if removed) and reconnect all connectors.

4. Clear Codes and Test Drive

• Tools Required: OBD-II scanner
• Reconnect the battery.
• Use the OBD-II scanner to clear the engine codes.
• Start the engine and allow it to reach normal operating temperature.
• Take the vehicle for a test drive to verify the repair.