how to fix P0303 code in Honda Civic 11th Generation (2022-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• 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

• Tools Required: Socket set, torque wrench, spark plug socket
• Remove the ignition coil from cylinder 3:
  1. Unplug the electrical connector from the ignition coil.
  2. Remove the bolts securing the ignition coil using a socket wrench.
  3. Gently pull out the ignition coil.
• Remove the spark plug:
  1. Use the spark plug socket to unscrew the spark plug from cylinder 3.
  2. Inspect the spark plug for signs of wear, carbon buildup, or damage.
• Replace the spark plug if necessary:
  1. Install a new spark plug, ensuring it is gapped to manufacturer specifications (typically around 0.044 inches for Honda).
  2. Torque the spark plug to the manufacturer's specifications (usually 13-16 lb-ft).

3. Inspect and Replace Ignition Coil

• Check the ignition coil for cylinder 3:
  1. Inspect for cracks, corrosion, or signs of wear.
  2. If faulty, replace with a new ignition coil.
• Reinstall the ignition coil:
  1. Position the new ignition coil over the spark plug.
  2. Secure it with the bolts and reconnect the electrical connector.

4. Check Fuel Injector

• Tools Required: Fuel injector cleaning kit (if cleaning), or replacement injector
• Inspect the fuel injector for cylinder 3:
  1. Disconnect the fuel injector electrical connector.
  2. Remove the injector according to service manual instructions.
• Clean the injector or replace it if clogged or damaged.

5. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0303 code and other stored codes.