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

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a level surface and ensure the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Spark Plugs

• Using a socket set, remove the ignition coils from the spark plugs.
• Remove the spark plugs with a spark plug socket. Inspect for wear and carbon buildup.
• Replace any worn or damaged spark plugs with OEM parts.
• Reinstall the spark plugs and torque them to the manufacturer's specifications (typically 13-15 lb-ft).

3. Check and Replace Ignition Coils

• Visual inspection of the ignition coils for cracks or damage.
• If any coils are faulty, remove them using a socket set.
• Replace with new ignition coils, ensuring they are seated properly.
• Reconnect the electrical connectors securely.

4. Fuel System Inspection

• Attach a fuel pressure gauge to the fuel rail Schrader valve.
• Turn the ignition to the "ON" position (do not start) to check fuel pressure; it should match specifications (usually around 40-50 psi).
• If pressure is low, inspect and replace the fuel filter if necessary, and consider the fuel pump for replacement.

5. Check for Vacuum Leaks

• Inspect all vacuum hoses for cracks or disconnections.
• Use a smoke machine or carburetor cleaner to identify leaks; listen for hissing sounds around the intake manifold.
• Replace any damaged hoses and tighten loose connections.

6. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0300 code.
• Start the engine and check for any new codes.