how to fix P0303 misfire code in Volkswagen Golf MK7.5 (2020-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool before beginning work.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket
• Remove the engine cover (if applicable).
• Locate the spark plug for cylinder three.
• Use a spark plug socket to remove the old spark plug.
• Inspect the old spark plug for signs of wear.
• Install a new spark plug, ensuring it is gapped correctly to manufacturer specifications.
• Torque the spark plug to the manufacturer's specified value (usually around 20-25 Nm).

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set, torque wrench
• Locate the ignition coil for cylinder three.
• Disconnect the electrical connector from the ignition coil.
• Remove the ignition coil by unscrewing the retaining bolts.
• Install the new ignition coil, ensuring it is seated properly.
• Reconnect the electrical connector and torque the retaining bolts to manufacturer specifications.

4. Check and Replace Fuel Injector (if necessary)

• Tools Required: Fuel injector removal tool, socket set
• Locate the fuel injector for cylinder three.
• Disconnect the fuel injector electrical connector.
• Remove the fuel rail if necessary to access the injector.
• Carefully pull the injector out of its socket.
• Install a new fuel injector, ensuring proper alignment and seating.
• Reconnect the fuel injector electrical connector.

5. Reassemble and Reconnect

• Reinstall any components removed during the process (e.g., engine cover).
• Reconnect the battery.