how to fix P0302 misfire code on Toyota Highlander Fourth Generation (2020-present)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative terminal of the battery to prevent electrical shorts.
• Allow the engine to cool before beginning work.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the ignition coil cover if applicable.
• Disconnect the electrical connector from the ignition coil.
• Remove the bolts securing the ignition coil and carefully pull it out.
• Use a spark plug socket to remove the old spark plug from cylinder 2.
• Inspect the spark plug hole for debris and clean if necessary.
• Install a new spark plug to the manufacturer's specified gap (usually 0.044 inches).
• Torque the spark plug to the manufacturer’s specification (typically around 13 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Replace Ignition Coil

• Tools Required: Socket set, torque wrench.
• If the ignition coil was found defective during diagnostics, remove the coil as described above.
• Install the new ignition coil onto the spark plug, ensuring it seats properly.
• Secure it with bolts and torque to the manufacturer’s specification (usually around 7 lb-ft).
• Reconnect the electrical connector.

4. Clean or Replace Fuel Injector

• Tools Required: Fuel injector cleaning kit (if cleaning), socket set.
• Disconnect the fuel line and electrical connector from the fuel injector in cylinder 2.
• Remove any retaining clips and pull the fuel injector out.
• If cleaning, use a fuel injector cleaner; if replacing, install a new fuel injector.
• Reconnect the fuel line and electrical connector.

5. Reconnect Battery and Clear Codes

• Reconnect the negative terminal of the battery.
• Use an OBD-II scanner to clear the error codes from the ECU.