how to fix P0301 misfire code on Honda Civic 11th Generation (2022-Present)

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Locate the spark plug for cylinder 1.
  3. Remove the ignition coil by unscrewing the retaining bolts and gently pulling it out.
  4. Use a spark plug socket to remove the old spark plug.
  5. Inspect the old spark plug for wear or damage. If worn, replace it with a new spark plug (gapped appropriately).
  6. Reinstall the ignition coil and secure it with bolts.

3. Check and Replace Ignition Coil

• Sub-steps:
  1. If the spark plug is in good condition, test the ignition coil with a multimeter for resistance.
  2. If the coil is faulty, disconnect the wiring harness and remove the coil.
  3. Install the new ignition coil, ensuring it is seated properly.
  4. Reconnect the wiring harness.

4. Fuel Injector Inspection and Replacement

• Sub-steps:
  1. Remove the fuel rail by unscrewing the bolts and disconnecting the fuel line (ensure to relieve fuel pressure beforehand).
  2. Take out the fuel injector for cylinder 1.
  3. Inspect the injector for clogs or damage. Replace if necessary.
  4. Reinstall the injector with new O-rings and reattach the fuel rail.

5. Perform Compression Test

• Sub-steps:
  1. Remove the spark plug from cylinder 1.
  2. Insert a compression gauge into the spark plug hole.
  3. Crank the engine a few times and record the compression reading.
  4. If the reading is below specifications, further engine inspection may be required.