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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative terminal of the battery to prevent electrical shorts.
• Allow the engine to cool before starting any repairs.

2. Inspect and Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, gap gauge.
• Remove the ignition coil for cylinder 2.
• Remove the spark plug using the spark plug socket.
• Inspect the spark plug for wear or damage; if necessary, replace it with a new one, ensuring the gap is set according to specifications (usually 0.043 inches for Toyota engines).
• Reinstall the spark plug and ignition coil.

3. Test and Replace Ignition Coil

• Tools Required: Multimeter.
• Disconnect the ignition coil connector from cylinder 2.
• Use a multimeter to measure the resistance of the ignition coil (refer to manufacturer specifications).
• If the resistance is out of specification, replace the ignition coil with a new one.
• Reconnect the ignition coil after replacement.

4. Inspect and Clean/Replace Fuel Injector

• Tools Required: Fuel injector cleaning kit or replacement injector.
• Disconnect the fuel line and electrical connector from the fuel injector in cylinder 2.
• Remove the fuel injector from its rail.
• Inspect for clogs; if necessary, clean using a fuel injector cleaning kit or replace it with a new injector.
• Reinstall the injector and reconnect the fuel line and electrical connector.

5. Verify Compression

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 2.
• Insert the compression tester into the spark plug hole.
• Crank the engine and record the compression reading.
• Compare the reading against manufacturer specifications; if low, further engine diagnostics may be needed.