how to diagnose a P0302 code in my Toyota Corolla E140 (2006-2013)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket
• Remove the engine cover if applicable.
• Use the spark plug socket to remove the spark plug from cylinder 2.
• Inspect the spark plug for wear, carbon buildup, or damage. If it’s worn, replace it with a new one.
• Gap the new spark plug to the manufacturer's specifications (typically around 0.043 inches for the Corolla).
• Reinstall the spark plug and tighten it to the manufacturer's torque specifications (usually around 13 lb-ft).

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set, multimeter
• Disconnect the electrical connector from the ignition coil on cylinder 2.
• Remove the ignition coil from cylinder 2 using the socket set.
• Test the ignition coil with a multimeter to ensure it is functioning correctly (check the primary and secondary resistance according to service manual specifications).
• If faulty, replace the ignition coil with a new one and reinstall it.

4. Check and Clean Fuel Injector

• Tools Required: Fuel injector cleaning kit or replace injector
• Remove the fuel injector from cylinder 2 using appropriate tools.
• Inspect for clogs or damage. If dirty, clean it using a fuel injector cleaner kit or replace it with a new injector.
• Reinstall the fuel injector and ensure it is seated properly.

5. Perform Compression Test

• Tools Required: Compression tester
• Remove the spark plug from cylinder 2 and connect the compression tester.
• Crank the engine and record the compression reading.
• Compare the reading to the specifications in the service manual. If the compression is low, further investigation for internal engine issues may be necessary.