how to fix P0301 misfire code on Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery cable to prevent electrical shock.
• Ensure the engine is cool before starting work.

2. Replace Spark Plug

• Remove the engine cover if necessary using a socket set.
• Locate the spark plug for cylinder 1, typically found near the front of the engine.
• Use a spark plug socket to remove the old spark plug.
• Inspect the new spark plug for the correct gap and specifications.
• Install the new spark plug by hand, then tighten it to the manufacturer’s torque specification (usually around 13-16 lb-ft).
• Reinstall the engine cover if removed.

3. Replace Ignition Coil

• Disconnect the electrical connector from the ignition coil for cylinder 1.
• Remove the retention bolt using a socket set and pull the ignition coil out.
• Install the new ignition coil and secure it with the bolt.
• Reconnect the electrical connector.

4. Inspect/Replace Fuel Injector

• Locate the fuel injector for cylinder 1.
• Disconnect the electrical connector and fuel line (ensure fuel pressure is relieved).
• Remove the injector retaining clips and pull the injector out.
• Check the injector for clogs; replace if necessary.
• Install the new fuel injector and reconnect the fuel line and electrical connector.

5. Verify Compression

• Remove the spark plug from cylinder 1 (if not already done).
• Insert a compression tester into the spark plug hole.
• Crank the engine to read the compression value, which should be within manufacturer specifications (often 180-220 psi).
• If compression is low, further diagnosis of piston rings or valves may be necessary.