how to fix the P0300 code on my Toyota RAV4 XA50 (2019-2024)

Solution

1. Preparation

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

2. Inspect and Replace Spark Plugs

• Tools Required: Spark plug socket, ratchet, torque wrench.
• Remove the engine cover if necessary.
• Using the spark plug socket, carefully remove each spark plug.
• Inspect the spark plugs for wear or fouling. Replace any damaged plugs with OEM parts.
• Torque new spark plugs to the manufacturer's specifications (typically around 13-15 ft-lbs).

3. Check and Replace Ignition Coils

• Tools Required: Ratchet, socket set.
• Disconnect the electrical connector from each ignition coil.
• Remove the ignition coils by unscrewing the retaining bolts.
• Test each coil’s resistance with a multimeter; replace any faulty coils.
• Reinstall the new coils and reconnect the electrical connectors.

4. Inspect and Clean Fuel Injectors

• Tools Required: Fuel injector cleaner, cleaning kit (if necessary).
• Remove the fuel rail if needed to access the injectors.
• Clean the fuel injectors using a fuel injector cleaner or replace them if they are clogged or damaged.
• Reassemble the fuel rail and ensure all connections are secure.

5. Check for Vacuum Leaks

• Inspect all vacuum hoses for cracks or disconnections.
• Use a spray of carburetor cleaner around the intake manifold to identify leaks (engine should idle rougher if a leak is present).
• Replace any damaged hoses or gaskets.

6. Test Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Connect the fuel pressure gauge to the fuel rail.
• Turn the ignition to the ON position (do not start the engine) and check the fuel pressure; it should match the specifications in the service manual.
• If pressure is low, inspect the fuel pump and filter for issues and replace if necessary.