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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool down before working on it.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, gap tool.
• Remove the ignition coil cover if necessary.
• Unscrew the spark plug from cylinder 1 using a socket and ratchet.
• Inspect the spark plug for wear; if damaged, replace it with a new one.
• Ensure the new spark plug is gapped correctly to manufacturer specifications (typically around 0.043 inches for Toyota).
• Reinstall the spark plug and torque it to the manufacturer’s specification (usually around 13 lb-ft).

3. Test and Replace Ignition Coil

• Tools Required: Multimeter.
• Disconnect the ignition coil connector from cylinder 1.
• Use a multimeter to check the resistance of the ignition coil; compare with manufacturer specifications.
• If the coil is faulty, remove it and replace it with a new ignition coil.
• Reconnect the ignition coil connector.

4. Inspect and Clean/Replace Fuel Injector

• Tools Required: Fuel injector cleaning kit or replacement injector, safety glasses.
• Disconnect the fuel line to the injector and the electrical connector.
• Remove the fuel injector from cylinder 1 by unscrewing any retaining clips.
• Inspect the injector for clogs; if necessary, clean it or replace it with a new injector.
• Reinstall the injector, ensuring all connections are secure.

5. Perform Compression Test

• Tools Required: Compression gauge.
• Remove the spark plug from cylinder 1.
• Insert the compression gauge into the spark plug hole.
• Crank the engine and record the compression reading; it should meet manufacturer specifications (around 150 PSI).
• If compression is low, further mechanical inspection is required.