how to fix P0303 misfire code on my Honda CR-V Fifth Generation (2017-2022)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shock.
• Allow the engine to cool down before starting work.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 3:
  • Unplug the electrical connector.
  • Unscrew the retaining bolt and carefully pull out the ignition coil.
• Remove the spark plug using a spark plug socket:
  • Clean any debris around the spark plug area before removal.
• Inspect the spark plug for wear, carbon buildup, or damage.
• Replace with a new spark plug of the correct type and gap (typically NGK or Denso).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Inspect and Replace Ignition Coil (if necessary)

• If the ignition coil shows signs of damage or has high resistance:
  • Use a multimeter to test the coil's resistance according to manufacturer specifications.
• Replace the ignition coil with a new one if it fails the test:
  • Position the new ignition coil and secure it with the retaining bolt.
  • Reconnect the electrical connector.

4. Inspect and Replace Fuel Injector (if necessary)

• If the fuel injector is suspected to be faulty:
  • Remove the fuel rail and unplug the fuel injector electrical connector.
  • Remove the fuel injector from the rail.
• Inspect for clogs or signs of damage. Clean or replace the injector as needed.
• Reinstall the fuel injector and fuel rail.

5. Perform Compression Test (if misfire persists)

• Remove the spark plugs from all cylinders for accurate testing.
• Insert the compression tester into the cylinder 3 spark plug hole.
• Crank the engine and record the compression reading.
• Compare the reading to the manufacturer's specifications. If low, further investigation is necessary (e.g., valve issues, head gasket failure).