how to fix P0302 misfire code in Toyota Highlander XU70 (2020-Present)

Solution

1. Preparation

• Gather tools and parts needed.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool if it was recently running.

2. Inspect and Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench.
• Remove the ignition coil from cylinder 2 by unscrewing its mounting bolts and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket and ratchet.
• Inspect the spark plug for wear, cracks, or carbon buildup. Replace if necessary.
• Install the new spark plug by hand, then torque to manufacturer specifications (typically around 13-15 ft-lbs).
• Reinstall the ignition coil, ensuring a secure connection.

3. Check and Replace Ignition Coil (if necessary)

• If the ignition coil appears damaged or worn, replace it.
• Remove the faulty ignition coil and install the new unit by reversing the removal steps.
• Ensure electrical connectors are secure.

4. Inspect and Clean Fuel Injector (if necessary)

• Tools Required: Fuel injector cleaner or replacement injector.
• Disconnect the fuel injector connector and remove the injector from the fuel rail.
• If cleaning, soak the injector in a fuel injector cleaner solution for the recommended time.
• Reinstall the injector (or replace if faulty) and ensure it is properly seated.

5. Verify Compression (if misfire persists)

• Tools Required: Compression gauge.
• Remove the spark plug from cylinder 2.
• Insert the compression gauge into the spark plug hole, and crank the engine.
• Compare the compression reading to manufacturer specifications; low compression may indicate internal engine issues.