how to fix P0300 misfire code in Honda Accord 10th Generation (2018-2022)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the engine is cool before beginning work.

2. Inspect and Replace Spark Plugs

• Remove the engine cover if applicable.
• Disconnect the ignition coil connectors.
• Remove the ignition coils using a socket set.
• Inspect the spark plugs for wear; replace if necessary.
  • Torque specification for spark plugs: 13 lb-ft (17.5 Nm).
• Install new spark plugs, ensuring they are properly gapped.
• Reinstall ignition coils and reconnect the connectors.

3. Check and Replace Ignition Coils

• If multiple cylinders are misfiring, test the ignition coils with a multimeter for resistance.
• Replace any faulty coils with new OEM parts.
• Reinstall the ignition coils in their respective positions.

4. Inspect Fuel Injectors

• Check fuel injector operation by using a noid light or listening for clicking sounds while the engine is running.
• If injectors are faulty, remove and replace them, ensuring proper sealing.
• Clean the injector ports before installation.

5. Address Vacuum Leaks

• Visually inspect all vacuum hoses for cracks or disconnections.
• Replace any damaged hoses.
• Use a smoke machine to find hard-to-detect leaks.

6. Reassemble and Test

• Reinstall any engine covers and reconnect the negative battery terminal.
• Start the engine and monitor for any misfire codes or symptoms.