how to fix P0302 misfire code on my Toyota Highlander Third Generation (2014-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shock.
• Allow the engine to cool before working on components.

2. Inspect and Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench, gap gauge.
• Remove the ignition coil cover if applicable.
• Unscrew and remove the spark plug from cylinder 2.
• Inspect the spark plug for wear, carbon buildup, or damage.
• If necessary, replace the spark plug with a new one, ensuring the gap is set to the manufacturer’s specification (typically around 0.043 inches).
• Reinstall the spark plug and torque to the manufacturer’s specifications (usually about 13-15 lb-ft).

3. Inspect and Replace Ignition Coil

• Tools Required: Ratchet, socket set.
• Remove the ignition coil from cylinder 2 by unscrewing the mounting bolts.
• Inspect the ignition coil for cracks or damage.
• If the coil is faulty, replace it with a new ignition coil.
• Reinstall the ignition coil and reconnect the electrical connector.

4. Check and Clean Fuel Injector

• Tools Required: Fuel injector cleaner, specialized fuel injector tool (if needed).
• Disconnect the fuel line and electrical connector from the fuel injector on cylinder 2.
• Remove the fuel injector from its rail.
• Clean the fuel injector using a fuel injector cleaning tool or replace it if malfunctioning.
• Reinstall the fuel injector and reconnect all lines.

5. Compression Test

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 2.
• Insert the compression tester into the spark plug hole.
• Crank the engine to take a compression reading.
• Compare the readings to the manufacturer’s specifications. If the compression is low, further investigation into the piston rings or valves may be necessary.