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

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1:
  • Use a socket set to remove the bolts securing the ignition coil.
  • Carefully lift the coil out of the spark plug well.
• Remove the spark plug:
  • Use a spark plug socket to unscrew the spark plug from cylinder 1.
  • Inspect for wear or damage and replace if necessary.
• Install the new spark plug:
  • Torque the new spark plug to 13 lb-ft (17.6 Nm).
• Reinstall the ignition coil:
  • Secure the coil in place with its bolts and reconnect the electrical connector.

3. Check and Replace Ignition Coil (if necessary)

• If the ignition coil was found to be faulty during inspection:
  • Remove the old coil as described in the previous step.
  • Install the new ignition coil.
  • Reconnect the electrical connector and ensure it clicks into place.

4. Inspect and Replace Fuel Injector (if necessary)

• Remove the fuel rail to access the fuel injector:
  • Relieve fuel pressure by removing the fuel pump fuse and starting the engine until it stalls.
  • Disconnect the fuel line (use a fuel line tool if necessary).
  • Remove the bolts securing the fuel rail and gently pull it away.
• Replace the injector if it was clogged or malfunctioning:
  • Remove the old injector from the rail and install the new one.
  • Reattach the fuel rail and reconnect the fuel line.

5. Verify Repair

• Reconnect the negative battery terminal.
• Start the engine and monitor for smooth operation.
• Check for any new or returning trouble codes with the OBD-II scanner.