how to fix a P0301 misfire code on Toyota Tacoma N300 (2016-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts while working on the ignition system.
• Ensure the engine is cool prior to working on any components.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1 by unbolting it and disconnecting the electrical connector.
• Extract the spark plug using a spark plug socket and ratchet.
• Inspect the spark plug for wear or damage; if necessary, replace with a new spark plug that meets OEM specifications (typically NGK or Denso).
• Torque the new spark plug to manufacturer specifications (usually around 13-15 lb-ft).

3. Test and Replace Ignition Coil (if necessary)

• If the spark plug is in good condition, test the ignition coil by swapping it with a known good coil from another cylinder.
• Clear the P0301 code and see if the misfire code moves to the other cylinder.
• If the misfire code follows the coil, replace the ignition coil with an OEM part.
• Reinstall the ignition coil after confirming it is functioning correctly.

4. Inspect Fuel Injector

• Remove the fuel injector from cylinder 1 after disconnecting the fuel rail.
• Inspect the injector for clogs or leaks. Clean or replace if necessary.
• Reinstall the injector and ensure all connections are secure.

5. Reassemble and Test

• Reconnect the battery.
• Start the engine and allow it to reach operating temperature.
• Monitor for any misfire codes or symptoms.