how to fix a misfire in Honda Accord with P0303 code

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down before working on it.

2. Inspect and Replace Spark Plug

• Sub-steps:
  • Remove the ignition coil from cylinder 3 by unscrewing the retaining bolts.
  • Pull the ignition coil straight out and inspect it for cracks or burn marks.
  • Remove the spark plug using a spark plug socket and ratchet.
  • Inspect the spark plug for wear; replace it if the gap is incorrect or if the insulator is damaged.
  • Install a new spark plug to the specified torque (typically 13-16 ft-lbs).
  • Reinstall the ignition coil, ensuring it clicks into place and is secured.

3. Inspect and Replace Ignition Coil (if necessary)

• Sub-steps:
  • If the ignition coil was found to be defective, replace it with a new one.
  • Ensure the new coil is compatible with the Honda Accord model.
  • Connect the electrical connector and secure the ignition coil.

4. Check and Replace Fuel Injector (if necessary)

• Sub-steps:
  • If the fuel injector is suspected to be faulty, remove the fuel rail to access the injector.
  • Disconnect the electrical connector and fuel line from the injector.
  • Remove the retaining clips and pull out the injector.
  • Replace with a new injector and ensure proper seating.
  • Reassemble the fuel rail and reconnect the fuel line and electrical connector.

5. Clear Error Codes

• Use the OBD-II scanner to clear the P0303 code from the engine control module (ECM).
• Reconnect the negative battery terminal.