how to fix P0300 misfire code in Toyota Corolla E210 (2019-2024)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plugs

• Tools Required: Socket set, torque wrench
• Remove the engine cover if applicable.
• Use a ratchet and socket to remove the spark plug wires or ignition coils.
• Carefully unscrew and remove the old spark plugs.
• Inspect the plug threads for damage; clean or replace as necessary.
• Install new spark plugs by hand to avoid cross-threading, then tighten to the manufacturer’s specified torque (typically 13-18 lb-ft).
• Reattach the ignition coils or spark plug wires securely.

3. Inspect and Replace Ignition Coils

• Tools Required: Socket set
• Disconnect the electrical connectors from each ignition coil.
• Remove the bolts securing the ignition coils to the engine.
• Pull out the ignition coils and inspect for damage or wear.
• Install new ignition coils in reverse order, ensuring they are securely fastened.

4. Clean or Replace Fuel Injectors

• Tools Required: Fuel injector cleaner kit or replacement injectors
• Remove the fuel rail by disconnecting the fuel line (use caution as fuel may spill).
• Remove the fuel injectors from the fuel rail.
• Clean the injectors using a fuel injector cleaning kit or replace them if they are faulty.
• Reinstall the injectors and fuel rail, ensuring all connections are tight.

5. Check Vacuum Lines and Intake Manifold

• Tools Required: Vacuum gauge (if needed)
• Visually inspect all vacuum hoses for cracks or disconnections.
• Replace any damaged vacuum lines.
• Check the intake manifold gaskets for proper sealing and replace if necessary.