how to fix a misfire code P0301 for my Toyota Tacoma N300 (2016-Present)?

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to prevent electrical shock.
• Allow the engine to cool down before starting work.

2. Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench, gap tool
• Remove the ignition coil from cylinder 1 by unscrewing its mounting bolt and disconnecting the electrical connector.
• Remove the spark plug using the spark plug socket.
• Inspect and clean the spark plug hole to prevent debris from entering the combustion chamber.
• Check the gap of the new spark plug using the gap tool and adjust to the manufacturer’s specification (usually around 0.043 inches for Toyota).
• Install the new spark plug and torque it to the manufacturer’s specification (typically 13 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Inspect and Replace Ignition Coil

• If the ignition coil appears damaged or the misfire persists, replace it with a new one.
• Unbolt the ignition coil and lift it out. Install the new ignition coil in reverse order of removal.
• Ensure the coil is seated properly and reconnect the electrical connector.

4. Check Fuel Injector (if necessary)

• If issues persist, check the fuel injector for cylinder 1.
• Remove the fuel rail to access the injector. Inspect or replace if clogged or malfunctioning.
• Clean the injector using a fuel injector cleaner or replace it if necessary.

5. Compression Test

• If misfire continues, perform a compression test on cylinder 1.
• Remove spark plugs and connect the compression tester to cylinder 1.
• Crank the engine and check the compression reading. It should meet the manufacturer's specification (usually around 150-200 psi).
• If readings are low, further internal engine diagnostics may be required.