how to fix P0300 random misfire code in my Toyota Camry Seventh Generation (2012-2017)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool down if it has been running.

2. Replace Spark Plugs

• Remove the ignition coils by unscrewing the mounting bolts and disconnecting the electrical connectors.
• Remove the spark plugs using a spark plug socket and ratchet.
• Inspect the old spark plugs for wear; replace them with new ones, ensuring to use the correct gap specification.
• Reinstall the ignition coils and reconnect the electrical connectors.

3. Inspect and Replace Ignition Coils (if necessary)

• If any ignition coils were found faulty during the inspection, remove them as described above.
• Install new ignition coils at the specified torque (generally around 10-12 lb-ft).
• Ensure all connectors are securely attached.

4. Check Fuel Injectors

• Disconnect the fuel injector connectors and remove the fuel rail if necessary.
• Inspect the injectors for clogs; clean or replace them if they are found to be faulty.
• Reinstall the fuel rail and connectors, ensuring there are no leaks.

5. Inspect for Vacuum Leaks

• Use a smoke machine or carburetor cleaner to identify any vacuum leaks in the intake manifold or associated hoses.
• Repair or replace any damaged hoses or gaskets as needed.

6. Final Checks

• Reconnect the battery terminal.
• Start the engine and allow it to reach normal operating temperature.