how to fix P0304 code in my Honda Accord 10th Generation (2018-2022) misfire on cylinder 4

Learn how to diagnose and fix P0304 cylinder 4 misfire in Honda Accord 10th Generation. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather required tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plug (if necessary)

• Tools Required: Spark plug socket, ratchet, torque wrench
• Remove the ignition coil by unbolting it and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket.
• Inspect the old spark plug for wear; replace if necessary with OEM specifications.
• Install the new spark plug and torque it to the manufacturer’s specification (typically 13-16 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Replace Ignition Coil (if necessary)

• Tools Required: Socket set, ratchet
• If the ignition coil is faulty, remove it from cylinder 4 by unbolting it and disconnecting the electrical connector.
• Install the new ignition coil ensuring it is seated properly and secure it with bolts.
• Reconnect the electrical connector.

4. Inspect and Repair Fuel Injector (if necessary)

• Tools Required: Fuel injector cleaner, noid light, multimeter
• Check the fuel injector for cylinder 4 using a noid light to verify electrical signal.
• If the signal is absent, trace wiring for damage; repair or replace as needed.
• If the injector is faulty, remove it and replace with a new one, ensuring proper seating and connection.