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

Solution

1. Preparation

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

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket, dielectric grease.
• Remove the ignition coil from cylinder 1 by unscrewing the bolts and gently pulling it out.
• Use the spark plug socket to remove the old spark plug. Inspect it for damage or excessive wear.
• Apply a small amount of dielectric grease to the threads of the new spark plug for easier installation.
• Install the new spark plug into cylinder 1 by hand, then torque it to the manufacturer specifications (typically around 13 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Test Ignition Coil

• Tools Required: Multimeter.
• Disconnect the ignition coil connector.
• Set the multimeter to measure resistance and check the primary and secondary windings against manufacturer specifications.
• Replace the ignition coil if it is outside of specifications.

4. Inspect Fuel Injector

• Tools Required: Fuel injector cleaning kit, O-ring replacements.
• Disconnect the fuel injector connector.
• Remove the fuel injector from cylinder 1.
• Inspect the injector for clogs; clean it using a fuel injector cleaning kit if necessary.
• Reinstall the fuel injector with new O-rings.

5. Check Compression

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 1 and install the compression tester.
• Crank the engine and note the compression reading; compare it to manufacturer specifications (usually around 150-200 psi).
• If compression is low, further engine diagnostics may be needed.