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

Solution

1. Preparation

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

2. Inspect and Replace Spark Plugs

• Remove the ignition coils using a socket set.
• Unscrew and remove the spark plugs.
  • Tools Required: Socket set, spark plug socket, torque wrench.
• Inspect each spark plug for wear or fouling; replace if necessary.
• Install new spark plugs and torque to manufacturer specifications (typically around 13-16 lb-ft).

3. Check and Replace Ignition Coils (if necessary)

• Remove the ignition coils from the cylinder head.
• Test each coil with a multimeter to ensure it is within specifications (consult service manual for values).
• Replace any faulty ignition coils with new ones.
• Reinstall the ignition coils and ensure they are seated properly.

4. Clean or Replace Fuel Injectors

• If fuel injectors are clogged, use a fuel injector cleaner or replace them.
• To replace, disconnect the fuel lines and electrical connectors.
• Remove the fuel rail and extract the injectors.
• Install new or cleaned injectors and reassemble the fuel rail.

5. Vacuum Leak Inspection

• Visually inspect all vacuum hoses connected to the intake manifold.
• Replace any cracked or damaged hoses.
• Use a smoke test if necessary to identify subtle leaks.

6. Engine Compression Test (if misfires persist)

• Remove spark plugs and perform a compression test on each cylinder.
• Record the values; they should be within manufacturer specifications.
• If readings are low, further investigation into the internal engine components may be necessary.