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

Solution

1. Preparation

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

2. Replace Spark Plugs

• Remove the ignition coil covers (if applicable) using a socket set.
• Disconnect the electrical connectors from the ignition coils.
• Remove the ignition coils using a socket and ratchet.
• Remove old spark plugs using a spark plug socket.
• Install new spark plugs, hand-tighten, and then torque to manufacturer specifications (typically around 13-15 ft-lbs).
• Reinstall the ignition coils and reconnect the electrical connectors.

3. Inspect and Replace Ignition Coils (if needed)

• If any ignition coils were found faulty during testing, remove them as described above.
• Install new ignition coils, ensuring they are seated properly.
• Reconnect the electrical connectors to the coils.

4. Fuel Injector Cleaning/Replacement

• If fuel injectors are clogged, remove them using a fuel injector puller.
• Clean the fuel injectors using a professional cleaning kit or replace them with new components.
• Reinstall the cleaned or new fuel injectors, ensuring proper seating and connection.

5. Vacuum Leak Repair

• Inspect all vacuum lines connected to the intake manifold for cracks or disconnections.
• Replace any damaged vacuum hoses with new ones.
• If a leak is found in the intake manifold gasket, replace the gasket by removing the intake manifold.

6. Fuel Pressure Check

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition key to the "On" position (do not start the engine) and check the fuel pressure reading.
• Compare the reading to manufacturer specifications (usually around 30-40 psi). Replace the fuel pump or filter if pressure is low.