how to fix P0303 code on Honda Accord 10th Generation (2018-2022)

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool down before starting work.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 3:
  • Unscrew any mounting bolts securing the coil.
  • Gently pull the coil out of the spark plug well.
• Remove the spark plug using a spark plug socket:
  • Turn counterclockwise until it is free.
• Inspect the spark plug for wear or damage (e.g., carbon buildup, electrode wear).
• Install a new spark plug (use OEM specifications):
  • Torque to manufacturer specifications (typically 13-16 lb-ft).

3. Inspect and Replace Ignition Coil

• Test the ignition coil’s resistance with a multimeter:
  • Check primary and secondary resistance according to service manual specifications.
• If out of specifications, replace the ignition coil:
  • Install the new coil onto the spark plug.
  • Secure with mounting bolts and reconnect the electrical connector.

4. Inspect and Clean Fuel Injector

• If the injector is not functioning, remove the fuel rail:
  • Relieve fuel pressure by removing the fuel pump fuse and starting the engine until it stalls.
  • Disconnect fuel lines and electrical connectors.
  • Remove the fuel rail assembly with injectors attached.
• Remove the injector from the rail and clean or replace it as necessary.
• Reinstall the rail and reconnect all lines and connectors.

5. Reassemble and Reconnect Battery

• Reinstall any removed components in reverse order.
• Reconnect the negative battery terminal.

6. Clear Codes and Test Drive

• Use the OBD-II scanner to clear all error codes.
• Start the engine and let it idle; check for any reoccurring codes.
• Take the vehicle for a test drive to ensure proper operation.