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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shocks.

2. Inspect and Replace Ignition Coil

• Tools Required: Socket set, torque wrench
• Remove the engine cover if applicable.
• Disconnect the electrical connector from the ignition coil on cylinder 1.
• Remove the bolts securing the ignition coil using a socket.
• Pull the ignition coil out gently to avoid damage.
• Install the new ignition coil by reversing the removal steps. Torque bolts to manufacturer specifications.

3. Inspect and Replace Spark Plug

• Tools Required: Spark plug socket, gap gauge
• Remove the ignition coil as described above to access the spark plug.
• Use a spark plug socket to unscrew and remove the old spark plug.
• Inspect the old spark plug for signs of wear or fouling.
• Set the gap on the new spark plug to the manufacturer's specifications.
• Install the new spark plug and torque to specifications.
• Reinstall the ignition coil.

4. Check and Clean Fuel Injector

• Tools Required: Fuel injector cleaner or ultrasonic cleaner (if required)
• Remove the fuel rail if necessary to access the fuel injector for cylinder 1.
• Disconnect the fuel line and the electrical connector from the injector.
• Remove the injector from the rail.
• Clean the injector using a suitable fuel injector cleaner.
• Reinstall the injector and reconnect the electrical connector and fuel line.

5. Check for Vacuum Leaks

• Tools Required: Smoke machine or carburetor cleaner
• Inspect hoses and the intake manifold for any visible cracks or loose connections.
• Use a smoke machine to find leaks or spray carburetor cleaner around suspected areas to see if the idle changes.
• Seal any leaks found or replace damaged hoses.