how to fix the P0301 misfire code in my Toyota Corolla E170 (2013-2019)?

Solution

1. Preparation

• Gather tools and parts necessary for repair.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool before starting work.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Disconnect the ignition coil connector for cylinder 1.
  3. Remove the ignition coil using a socket.
  4. Extract the old spark plug using a spark plug socket.
  5. Inspect the spark plug for wear or damage.
  6. Install a new spark plug, ensuring it is gapped according to manufacturer specifications (usually around 0.043 inches).
  7. Torque the spark plug to the manufacturer's specification (typically around 13 lb-ft).

3. Replace Ignition Coil (if necessary)

• Tools Required: Socket set.
• Sub-steps:
  1. If the spark plug replacement did not resolve the issue, proceed to replace the ignition coil.
  2. Remove the ignition coil from cylinder 1, noting the orientation.
  3. Install the new ignition coil and connect the ignition coil connector.
  4. Reinstall any components removed during the process.

4. Clean or Replace Fuel Injector (if necessary)

• Tools Required: Fuel injector removal tool.
• Sub-steps:
  1. If the issue persists, check the fuel injector for cylinder 1.
  2. Remove the fuel rail if necessary to access the injector.
  3. Clean the injector using a suitable fuel injector cleaner or replace it if defective.
  4. Reinstall the fuel rail and ensure all connections are tight.

5. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0301 code and other stored codes.