how to fix P0304 code in Honda Accord 9th Generation (2013-2017)

Learn how to diagnose and fix P0304 cylinder 4 misfire in Honda Accord 9th Generation (2013-2017). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts. Disconnect the battery to ensure safety during repairs.
• Tools Required: Socket set, multimeter, compression tester, OBD-II scanner, torque wrench.

2. Replace Spark Plug (if faulty)

• Remove the engine cover if applicable.
• Disconnect the ignition coil connector from the ignition coil on cylinder 4.
• Remove the ignition coil by unbolting it and gently pulling it out.
• Unscrew and remove the spark plug using a spark plug socket.
• Inspect the spark plug for wear or carbon buildup; replace if necessary.
• Install the new spark plug and torque to manufacturer specifications (typically 13-15 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Replace Ignition Coil (if faulty)

• If the ignition coil was found to be faulty during inspection, replace it with a new one.
• Install the new ignition coil and reconnect the electrical connector.
• Ensure all connections are secure and that the ignition coil is seated properly.

4. Check and Replace Fuel Injector (if faulty)

• If the fuel injector is suspected to be faulty, disconnect the injector connector.
• Remove the fuel injector using an injector puller if necessary.
• Install the new fuel injector, ensuring it seats correctly in the manifold.
• Reattach the injector connector and ensure it is secure.

5. Address Mechanical Issues (if necessary)

• If the compression test on cylinder 4 shows low readings, further investigation may be needed to check for issues such as a blown head gasket or valve problems.