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

Solution

1. Preparation

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

2. Replace Spark Plug and Ignition Coil

1. Remove the engine cover if applicable.
2. Locate the ignition coil for cylinder 1.
3. Disconnect the ignition coil connector.
4. Remove the ignition coil bolt using a socket wrench.
5. Pull the ignition coil out carefully.
6. Remove the spark plug using a spark plug socket and ratchet.
7. Inspect the old spark plug for wear; replace it with a new spark plug (check gap specifications).
8. Install the new spark plug and torque it to manufacturer specifications (usually around 13 lb-ft).
9. Reinstall the ignition coil and secure it with the bolt, then reconnect the ignition coil connector.

3. Clean or Replace Fuel Injector

1. Locate the fuel injector for cylinder 1.
2. Disconnect the fuel injector electrical connector.
3. Remove the fuel rail bolts and carefully lift the rail to access the injector.
4. Remove the fuel injector from the rail (may require a special tool).
5. Clean the injector with a fuel injector cleaner or replace it with a new injector.
6. Reinstall the fuel injector and ensure it is seated properly, then reattach the fuel rail.

4. Compression Test (if needed)

1. Remove the spark plug from cylinder 1.
2. Screw in the compression tester into the spark plug hole.
3. Crank the engine for several seconds while observing the gauge.
4. Note the compression reading; it should be within the manufacturer's specified range. If not, further engine diagnostics may be required.