my Honda Civic 11th Generation (2022-Present) has a check engine light with code P0301

Solution

1. Preparation

• Gather tools and parts necessary for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool before proceeding with repairs.

2. Inspect and Replace Spark Plug

• Remove the engine cover if applicable.
• Locate the spark plug for cylinder 1.
• Use a socket wrench to remove the spark plug.
  • Tools Required: Socket set, torque wrench
• Inspect the spark plug for wear or fouling.
• If damaged, replace with a new spark plug, ensuring it is gapped correctly.
• Torque the new spark plug to the manufacturer's specifications (typically around 13-16 lb-ft).

3. Inspect and Replace Ignition Coil

• Disconnect the electrical connector from the ignition coil for cylinder 1.
• Remove the ignition coil using a socket wrench.
• Inspect for cracks or corrosion.
• Replace with a new ignition coil if damaged.
• Reconnect the electrical connector securely.

4. Check and Replace Fuel Injector (if necessary)

• Disconnect the fuel injector connector for cylinder 1.
• Remove the fuel rail if necessary to access the injector.
• Remove the fuel injector using a suitable tool.
• Check for clogs or leaks in the injector.
• Replace with a new fuel injector if it fails the resistance test or shows signs of damage.
• Reinstall the fuel rail and reconnect the fuel injector connector.

5. Reassemble and Reconnect Battery

• Reinstall the engine cover if removed.
• Reconnect the negative battery terminal.
• Clear the error codes using the OBD-II scanner.