how to diagnose P0302 misfire code on Toyota Corolla E140 (2006-2013)

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Spark Plug

• Remove the spark plug from cylinder 2 using a socket wrench.
• Inspect for wear, carbon buildup, or damage.
• If necessary, replace with a new spark plug specified for the vehicle.
  • Torque the new spark plug to 13 lb-ft (17.5 Nm).

3. Check and Replace Ignition Coil

• Disconnect the ignition coil connector and remove the mounting bolts.
• Remove the ignition coil for cylinder 2.
• Test the ignition coil with a multimeter (primary resistance: 0.4-2 ohms; secondary resistance: 6-12 kohms).
• Replace the ignition coil if it is outside specifications.

4. Inspect and Clean Fuel Injector

• Disconnect the fuel injector connector.
• Remove the fuel injector from cylinder 2.
• Clean the injector using a fuel injector cleaning kit or replace it if clogged or defective.

5. Compression Testing

• Insert the compression tester into the spark plug hole of cylinder 2.
• Crank the engine several times and record the compression reading.
• If compression is below specifications (around 180 psi), further investigation of the internal engine components may be necessary.

6. Reassemble and Reconnect

• Reinstall any components that were removed during inspection.
• Reconnect the negative battery terminal.
• Ensure all connections are secure and there are no tools left in the engine bay.