how to fix P0301 misfire code in Honda Accord Eleventh Generation (2023-present)

Solution

1. Preparation

• Ensure the engine is off and cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug gap tool
• Remove the ignition coil cover if applicable.
• Disconnect the electrical connector from the ignition coil and remove the coil.
• Remove the spark plug using a spark plug socket.
• Inspect the spark plug for wear; if damaged or worn, replace it with a new spark plug that meets OEM specifications.
• Ensure the new spark plug is gapped correctly according to manufacturer specifications (typically around 0.043 inches for Honda).
• Reinstall the spark plug and torque it to the manufacturer's specifications (usually around 13 ft-lbs).

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set, torque wrench
• If the spark plug is in good condition, check the ignition coil.
• Swap the cylinder 1 ignition coil with another cylinder's coil (e.g., cylinder 2).
• Clear the codes and start the engine; if the misfire code follows the coil, replace the faulty ignition coil with a new one.
• Install the new ignition coil and torque it to the manufacturer’s specifications (typically around 70 in-lbs).

4. Inspect and Clean Fuel Injector

• Tools Required: Fuel injector cleaner, basic hand tools
• If the issue persists, check the fuel injector for cylinder 1.
• Disconnect the fuel injector connector and remove the fuel injector.
• Clean the injector with a fuel injector cleaning solution or replace it if clogged or malfunctioning.
• Reinstall the fuel injector and reconnect the electrical connector.

5. Compression Test

• Tools Required: Compression gauge
• Perform a compression test on cylinder 1 to check for mechanical issues.
• If compression is low, further diagnosis may be required, indicating possible issues with valves or piston rings.