how to fix P0304 misfire code in Volkswagen Golf Eighth Generation (2020-present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plug and Ignition Coil

• Tools Required: Socket set, torque wrench, dielectric grease.
• Remove the engine cover (if applicable) to access the ignition coils.
• Disconnect the wiring harness from the ignition coil for cylinder 4.
• Use a socket to remove the ignition coil from the cylinder head.
• Remove the spark plug using a spark plug socket and inspect for wear or damage.
• Install the new spark plug and torque it to the manufacturer’s specifications (typically around 15-20 ft-lbs).
• Apply dielectric grease to the new ignition coil connector, then install the coil and reconnect the wiring harness.

3. Inspect and Test Fuel Injector

• Tools Required: Noid light or multimeter, fuel pressure gauge (if needed).
• Disconnect the fuel injector connector for cylinder 4.
• Use a noid light to ensure the injector is receiving the correct pulse signal. If no signal, check the wiring.
• If the injector is faulty, replace it by removing the fuel rail (ensure fuel pressure is relieved before removal).
• Install the new injector and reconnect the connector.

4. Conduct Compression Test (if needed)

• Tools Required: Compression gauge.
• Remove the spark plug from cylinder 4.
• Insert the compression gauge into the spark plug hole and crank the engine several times.
• Compare the compression reading to the manufacturer’s specifications. If low, further engine diagnostics may be needed.