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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative terminal of the battery to ensure safety.

2. Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench.
• Remove the ignition coil cover if fitted.
• Disconnect the ignition coil connector and remove the ignition coil from cylinder 1.
• Remove the spark plug using a spark plug socket.
• Check the gap on the new spark plug and adjust it to the manufacturer's specifications (typically around 0.043 inches).
• Install the new spark plug and torque it to 13 lb-ft (18 Nm).
• Reinstall the ignition coil and connect the electrical connector.

3. Replace Ignition Coil (if necessary)

• If the ignition coil is found faulty during inspection, replace it.
• Tools Required: Socket set.
• Remove the ignition coil as described earlier.
• Install the new ignition coil and ensure it is seated properly.
• Reconnect the ignition coil connector.

4. Inspect and Clean Fuel Injector

• If the fuel injector is suspect, consider cleaning or replacing it.
• Tools Required: Fuel injector cleaner kit or replacement injector.
• Disconnect the fuel injector connector.
• Remove the fuel rail and injector assembly, taking care to prevent fuel spillage.
• Clean the injector using a dedicated cleaning kit or replace it if necessary.
• Reassemble the injector with O-rings lubricated with clean engine oil.

5. Compression Test (if needed)

• If misfire persists, perform a compression test on cylinder 1.
• Tools Required: Compression tester.
• Remove spark plug from cylinder 1.
• Insert the compression tester and crank the engine several times.
• Compare the reading to manufacturer specifications; replace the engine if compression is low.