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

Solution

1. Preparation

• Gather tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shock.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench
• Remove the engine cover (if applicable).
• Locate and remove the spark plug wire or ignition coil from cylinder 2.
• Use a spark plug socket to remove the old spark plug.
• Inspect the spark plug threads for damage; clean if necessary.
• Install the new spark plug by hand to avoid cross-threading, then torque to the manufacturer's specification (typically 13-15 lb-ft).

3. Check and Replace Ignition Coil (if necessary)

• Disconnect the ignition coil connector.
• Remove the ignition coil by unbolting it from the cylinder head.
• Compare the resistance of the ignition coil with specifications (usually 0.5-1.5 ohms for primary resistance).
• Install a new ignition coil if the resistance is outside specifications, ensuring it is properly seated and secured.

4. Inspect and Replace Fuel Injector (if necessary)

• Disconnect the fuel injector connector and remove the fuel rail (if applicable).
• Remove the fuel injector from cylinder 2.
• Check the injector for clogs or proper operation using a noid light.
• Replace the fuel injector with a new one if it fails the test.
• Reinstall the injector and ensure all connections are secure.

5. Perform Compression Test (if necessary)

• Remove spark plugs from cylinders 1 and 2 for a proper test.
• Insert the compression gauge into the cylinder 2 spark plug hole.
• Crank the engine to get a compression reading; it should be within manufacturer specifications (usually around 180-220 psi).
• If low, investigate further for potential issues such as head gasket failure or valve problems.