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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool down.

2. Replace Spark Plug

• Remove the ignition coil by unfastening the retaining bolt and disconnecting the electrical connector.
• Extract the old spark plug using a spark plug socket. Check the condition and gap specifications.
• Install a new spark plug, ensuring it’s properly gapped according to manufacturer specifications (typically 0.043 inches).
• Reattach the ignition coil, ensuring it is secure and the connector is properly seated.

3. Inspect and Replace Ignition Coil (if necessary)

• If the ignition coil shows signs of damage or the spark plug was excessively worn, replace the ignition coil for cylinder 1.
• Disconnect the electrical connector and remove the coil by unfastening any retaining bolts.
• Install the new ignition coil and reconnect the electrical connector.

4. Clean or Replace Fuel Injector (if necessary)

• If injector issues are suspected, remove the fuel injector from cylinder 1 by disconnecting the fuel line and electrical connector.
• Inspect the injector for clogs or debris. Clean using an appropriate fuel injector cleaner.
• If cleaning does not resolve issues, replace the fuel injector with a new one.

5. Check Compression (if necessary)

• Perform a compression test on cylinder 1 using a compression gauge.
• If compression is below specifications (typically 180 psi), further investigation into valve seating or piston rings may be necessary.