how do I fix the P0301 misfire code on my Honda Civic 10th Generation (2016-2021)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the engine is cool before beginning work.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench, dielectric grease.
• Sub-steps:
  1. Remove the ignition coil from cylinder 1 by unscrewing the retaining bolts and disconnecting the connector.
  2. Remove the spark plug using the spark plug socket.
  3. Inspect the spark plug for wear, carbon buildup, or damage. Replace if necessary.
  4. Apply dielectric grease to the new spark plug's threads to prevent seizing.
  5. Install the new spark plug and tighten to the manufacturer’s specified torque (typically around 13 lb-ft).
  6. Reinstall the ignition coil and reconnect the electrical connector.

3. Inspect and Replace Ignition Coil (if necessary)

• Tools Required: Socket set.
• Sub-steps:
  1. If the spark plug is not the issue, remove the ignition coil from cylinder 1.
  2. Inspect the ignition coil for cracks or damage.
  3. Replace with a new ignition coil if defects are found.
  4. Reinstall the ignition coil and connect the wiring harness.

4. Check Fuel Injector (if necessary)

• Tools Required: Fuel injector cleaner, socket set.
• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Remove the fuel injector using a socket set.
  3. Clean the injector using a fuel injector cleaner or replace it if clogged or malfunctioning.
  4. Reinstall the injector and reconnect the wiring.

5. Perform Compression Test (if necessary)

• Tools Required: Compression tester.
• Sub-steps:
  1. Remove the spark plug for cylinder 1.
  2. Insert the compression tester and crank the engine.
  3. Record the compression reading; it should be within the manufacturer’s specified range (typically 180-220 psi).
  4. If the compression is low, further investigation into piston rings or valve seals is needed.