how to deal with a P0300 code on my Toyota Corolla E140 (2006-2013)?

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Park the vehicle on a level surface and engage the parking brake.
• Disconnect the battery to prevent any electrical shorts.

2. Inspect and Replace Spark Plugs

• Remove the engine cover if applicable.
• Use a socket and ratchet to remove the spark plug wires or ignition coils.
• With a spark plug socket, carefully remove the spark plugs.
• Inspect each spark plug for wear; replace with OEM specification plugs if necessary (typically NGK or Denso).
• Reinstall spark plugs by hand, then torque to manufacturer specification (usually around 13-15 ft-lbs).

3. Check and Replace Ignition Coils

• If misfires persist after spark plug replacement, inspect ignition coils.
• Disconnect the electrical connector from each ignition coil.
• Remove the ignition coils using a socket and ratchet.
• Test each coil with a multimeter to ensure proper resistance (typically around 0.5-0.8 ohms).
• Replace any faulty ignition coils with OEM components.

4. Inspect Fuel Injectors

• If issues continue, inspect fuel injectors for proper operation.
• Remove the fuel rail if necessary to access injectors.
• Check for clogs using a fuel injector cleaning kit or replace with new injectors if needed.
• Reinstall the fuel rail ensuring no leaks.