how to resolve P0302 misfire code in Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Remove the engine cover if applicable.
• Use a socket set to disconnect the ignition coil from cylinder 2.
• Remove the spark plug using a spark plug socket.
• Inspect the spark plug for damage or excessive wear; replace with OEM specifications if necessary (e.g., NGK ILZKR7B11).
• Reinstall the spark plug and reconnect the ignition coil.

3. Check and Replace Ignition Coil

• If the spark plug is in good condition, test the ignition coil with a multimeter to check its resistance (specifications: primary resistance should be around 0.5-0.7 ohms, secondary around 10-15 k ohms).
• Replace the ignition coil if readings are outside specifications.
• Reconnect the ignition coil and ensure it is securely seated.

4. Inspect Fuel Injector

• Disconnect the fuel injector electrical connector.
• Use a multimeter to check the injector's resistance (should be around 12-16 ohms).
• If faulty, replace the injector with a new OEM part.
• Reconnect the fuel injector and ensure a secure connection.

5. Check for Vacuum Leaks

• Inspect vacuum lines around cylinder 2 for cracks or disconnections.
• Use a smoke machine or carburetor cleaner to check for leaks while the engine is running.
• Repair any identified leaks to ensure proper air-fuel mixture.