how to fix P0301 misfire code on Toyota Corolla E210 (2019-2024)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the engine is cool before starting any work.

2. Inspect and Replace Spark Plug

• Remove the engine cover if necessary to access the spark plug.
• Use a socket set to remove the spark plug from cylinder 1.
• Inspect the spark plug for wear, carbon buildup, or damage.
• If worn or damaged, replace it with a new spark plug (follow manufacturer specifications for part number and gap).
• Reinstall the spark plug and torque to the manufacturer's specifications (typically around 13-15 lb-ft).

3. Test and Replace Ignition Coil

• Disconnect the ignition coil connector and remove the ignition coil from cylinder 1.
• Inspect the coil for cracks or damage.
• Use a multimeter to test the resistance of the ignition coil (check service manual for specific resistance values).
• If defective, replace the ignition coil with a new one.
• Reinstall the ignition coil and reconnect the connector.

4. Inspect and Clean Fuel Injector

• Remove the fuel rail if necessary to access the fuel injector for cylinder 1.
• Disconnect the electrical connector and fuel line from the injector.
• Remove the fuel injector and inspect it for clogging or damage.
• Clean the injector using a fuel injector cleaner or replace it if necessary.
• Reinstall the injector ensuring proper alignment and secure the fuel line.

5. Recheck Compression

• If issues persist, perform a compression test on cylinder 1.
• If compression is low, it may indicate a more serious engine problem (e.g., valve issues, piston rings).
• Address any compression issues as necessary (this may require further engine disassembly).