how to fix P0304 misfire code on Honda CR-V Sixth Generation (2023-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to avoid electrical shock.
• Allow the engine to cool before starting work.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 4 using a socket set.
• Remove the spark plug from cylinder 4 using a spark plug socket.
• Inspect the spark plug for wear, carbon deposits, or damage.
• If necessary, replace the spark plug with a new one (OEM specifications recommended).
  • Torque the new spark plug to 13 lb-ft (18 Nm).
• Reinstall the ignition coil after inspection.

3. Inspect and Replace Ignition Coil

• If the spark plug is in good condition but the misfire persists, remove the ignition coil from cylinder 4.
• Inspect the ignition coil for cracks or damage.
• Replace the ignition coil if defective with an OEM or equivalent part.
• Ensure that the electrical connector is secure when reinstalling.

4. Test Fuel Injector

• Locate the fuel injector for cylinder 4.
• Disconnect the electrical connector from the fuel injector.
• Use a multimeter to test the fuel injector’s resistance; it should be within the manufacturer's specifications.
• If faulty, replace the fuel injector with a new one.
• Reconnect the electrical connector securely after replacement.

5. Compression Test

• If the issue persists after replacing the spark plug and ignition coil, perform a compression test on cylinder 4.
• If compression is low, further investigation may be necessary to determine if there are issues with the piston rings, valves, or head gasket.