how to fix my Honda Civic 10th Generation (2016-2021) engine misfire code P0302

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool before starting work.

2. Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench, gap gauge
• Remove the ignition coil from cylinder 2 by unscrewing the retaining bolt and disconnecting the electrical connector.
• Unscrew the spark plug using the spark plug socket and ratchet.
• Inspect the old spark plug and compare it to specifications; if it’s worn or fouled, replace it with a new spark plug.
• Use a gap gauge to ensure the new spark plug is gapped correctly according to manufacturer specifications (typically around 0.044 inches for Honda).
• Install the new spark plug, hand-tighten, then torque to specifications (typically around 13-16 lb-ft).

3. Inspect and Replace Ignition Coil

• Tools Required: Torque wrench, multimeter
• After removing the ignition coil, check for any signs of damage or corrosion.
• Test the ignition coil's resistance using a multimeter; it should be within manufacturer specifications.
• If faulty, replace the ignition coil with a new one specific to cylinder 2.
• Reinstall the ignition coil and secure it with the retaining bolt, ensuring it is torqued to the manufacturer's specifications.

4. Fuel Injector Cleaning or Replacement

• Tools Required: Fuel injector cleaner kit, socket set
• Disconnect the fuel injector connector and remove the fuel rail.
• Inspect the fuel injector for clogs or leaks. If clogged, clean it using a fuel injector cleaning kit.
• If cleaning does not resolve the issue, replace the fuel injector with a new one.
• Reassemble the fuel rail and reconnect the fuel injector connectors.