how to fix P0304 code in Honda Accord 10th Generation (2018-2022)

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 all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plug

1. Remove the engine cover if applicable.
2. Locate the spark plug for cylinder 4 (refer to the owner's manual for specific location).
3. Use a spark plug socket to remove the old spark plug.
4. Inspect the spark plug for signs of wear (e.g., fouling, damage).
5. Install a new spark plug, ensuring it is properly gapped (typically 0.044 inches for Honda).
6. Torque the spark plug to the manufacturer's specifications (approximately 13 lb-ft).

3. Inspect and Replace Ignition Coil

1. Disconnect the electrical connector from the ignition coil.
2. Remove the ignition coil retaining bolts using a socket wrench.
3. Pull the ignition coil straight out from the spark plug tube.
4. Install a new ignition coil, ensuring it fits snugly.
5. Reattach the ignition coil retaining bolts and torque them to specifications (generally 7 lb-ft).
6. Reconnect the electrical connector.

4. Clean or Replace Fuel Injector

1. Remove the intake manifold if necessary to access the fuel injector.
2. Disconnect the fuel line and electrical connector from the injector.
3. Remove the fuel injector retaining clips and pull the injector out.
4. Clean the injector using a specialized cleaner or replace it with a new one.
5. Reinstall the injector and reconnect the fuel line and electrical connector.

5. Reassemble and Test

1. Reinstall any components removed during the repair.
2. Reconnect the negative battery terminal.
3. Start the engine and let it idle to ensure smooth operation.