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

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal to prevent electrical shock.
• Allow engine to cool before starting work.

2. Replace Spark Plug

• Remove the engine cover if applicable using a socket set.
• Remove the ignition coil for cylinder 2 by unscrewing the retaining bolts and gently pulling it out.
• Remove the old spark plug using a spark plug socket. Inspect it for wear or damage.
• Install a new spark plug, applying the manufacturer’s recommended torque (typically around 13 lb-ft).
• Reinstall the ignition coil for cylinder 2 and reconnect it.

3. Inspect and Replace Ignition Coil

• If the spark plug appears fine, test the ignition coil with a multimeter for resistance; replace if out of specification.
• Install a new ignition coil by reversing the removal steps, ensuring it is securely fastened.

4. Check and Clean Fuel Injector

• If the ignition system is functioning correctly, disconnect the fuel injector connector.
• Using a fuel injector cleaning kit, clean the fuel injector for cylinder 2.
• Reconnect the fuel injector and check for proper operation.

5. Perform Compression Test

• If misfire persists, perform a compression test on cylinder 2.
• If compression is low, further investigation into the cylinder’s mechanical condition is required (e.g., valve issues, head gasket failure).