how to fix P0301 misfire code in my Toyota RAV4 XA50 (2019-2024)

Solution

1. Preparation

• Gather tools and parts required for repair.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool before starting work.

2. Inspect and Replace Spark Plug

• Remove the ignition coil by unbolting it and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket and ratchet.
• Inspect the spark plug for signs of fouling or wear; replace it if necessary with a new spark plug (OEM recommended).
• Torque the new spark plug to the manufacturer's specifications (typically around 13-15 lb-ft).
• Reinstall the ignition coil.

3. Check and Replace Ignition Coil

• If the spark plug is in good condition but the misfire persists, test the ignition coil with a multimeter.
• If the resistance is outside of the specified range, replace the ignition coil with a new one.
• Reinstall the ignition coil and reconnect the electrical connector.

4. Inspect and Clean/Replace Fuel Injector

• If the ignition system is functioning correctly, remove the fuel injector for cylinder 1.
• Inspect for clogs or debris; clean using a fuel injector cleaning kit if necessary.
• If cleaning does not resolve the issue, replace the fuel injector with a new one.

5. Compression Test

• If all previous steps do not resolve the misfire, perform a compression test on cylinder 1.
• If compression is low, further diagnostic work may be required to assess internal engine issues (e.g., valve or piston problems).