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

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket, compressed air.
• Remove the ignition coil from cylinder 1 by unscrewing the mounting bolts.
• Carefully pull out the spark plug using a spark plug socket.
• Inspect the spark plug for signs of wear, carbon buildup, or damage.
• If necessary, clean the cylinder head area with compressed air before installation.
• Install a new spark plug, ensuring it is gapped correctly to manufacturer specifications (typically 0.043 inches).
• Torque the spark plug to the manufacturer's specified value (usually around 13-16 ft-lbs).

3. Check and Replace Ignition Coil

• Tools Required: Socket set.
• Swap the ignition coil from cylinder 1 with another cylinder (e.g., cylinder 3).
• Clear the codes using the OBD-II scanner and start the engine.
• If the misfire moves to the other cylinder, replace the ignition coil.
• Install the new ignition coil onto cylinder 1 if necessary, securing it with bolts.

4. Inspect and Clean Fuel Injector

• Tools Required: Fuel injector cleaner kit (if using a cleaning solution), multimeter.
• Disconnect the fuel injector connector for cylinder 1.
• Test the injector's resistance with a multimeter; it should match manufacturer specifications (usually around 12-16 ohms).
• If out of range, replace the fuel injector.
• If within range, use a fuel injector cleaner to clean the injector while keeping the fuel system connected.

5. Compression Test

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 1 and connect the compression tester.
• Crank the engine to measure the compression.
• Compare the reading with manufacturer specifications (usually around 180-200 psi).
• If compression is low, further diagnosis may be needed for internal engine repairs.