how to fix P0302 misfire code in Honda Civic 9th Generation (2012-2015)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative terminal of the battery.
• Allow the engine to cool down completely before starting work.

2. Inspect and Replace Spark Plug

• Remove the engine cover (if applicable) using a socket set.
• Disconnect the ignition coil connector and remove the ignition coil using a socket set.
• Remove the spark plug using a spark plug socket and ratchet.
• Inspect the spark plug for wear; replace if necessary.
• Ensure the gap is set according to manufacturer specifications (typically around 0.044 inches).
• Install a new spark plug and reassemble the ignition coil and connector.

3. Check and Replace Ignition Coil

• If the spark plug is in good condition, check the ignition coil.
• If testing reveals a faulty ignition coil, replace it:
  • Disconnect the ignition coil connector.
  • Remove the ignition coil from the spark plug well.
  • Install the new ignition coil, reconnect the connector, and ensure it is seated properly.

4. Perform Compression Test

• Remove all spark plugs to ease compression testing.
• Insert the compression gauge into the cylinder 2 spark plug hole.
• Crank the engine for several revolutions and note the compression reading.
• Compare with manufacturer specifications (typically around 190 psi). If low, further inspection of valves and piston rings is needed.

5. Inspect Fuel Injector

• If compression is adequate, check the fuel injector:
  • Remove the injector connector.
  • Use a multimeter to check for proper resistance (usually between 12-16 ohms).
  • If the injector is faulty, replace it:
    • Remove the fuel rail (ensure to relieve fuel pressure first).
    • Replace the faulty injector and reassemble the fuel rail.