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

Solution

1. Preparation

• Gather tools and materials: OBD-II scanner, socket set, torque wrench, multimeter, new spark plug, new ignition coil (if necessary), and cleaning solvent for injectors.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover (if applicable) using a socket set.
  2. Locate the spark plug for cylinder 1 (typically at the front of the engine).
  3. Disconnect the ignition coil connector.
  4. Remove the ignition coil by unbolting it and pulling it straight out.
  5. Use a spark plug socket to remove the spark plug.
  6. Inspect the spark plug for wear or fouling; replace it if necessary with a new spark plug that meets OEM specifications.
  7. Reinstall the new spark plug and torque it to the manufacturer’s specifications (typically around 13-16 lb-ft).

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. If the ignition coil is damaged, replace it with a new coil.
  2. Ensure to use a coil compatible with your vehicle’s specifications.
  3. Reinstall the ignition coil by aligning it with the spark plug and securing it with bolts.
  4. Reconnect the ignition coil connector.

4. Inspect and Clean Fuel Injector

• Sub-steps:
  1. If the injector appears clogged, remove it following the manufacturer’s guidelines.
  2. Use a cleaning solvent to clean the fuel injector or replace it if it cannot be cleaned.
  3. Reinstall the cleaned or new fuel injector and ensure it is properly seated.

5. Reassemble and Reconnect Battery

• Sub-steps:
  1. Reinstall any components removed during the process, including the engine cover.
  2. Reconnect the battery terminals, ensuring a secure connection.