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

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, multimeter, compression tester.
• Gather necessary replacement parts (e.g., spark plug, ignition coil, fuel injector) based on diagnostic results.

2. Replace Spark Plug and Ignition Coil (if faulty)

1. Disconnect battery: Always disconnect the negative terminal before working on electrical components.
2. Remove engine cover: If applicable, use the socket set to remove any fasteners securing the engine cover.
3. Access cylinder 2 components: Locate cylinder 2's ignition coil and spark plug (typically, it's the second cylinder from the timing belt side).
4. Remove the ignition coil:
   • Disconnect the electrical connector from the ignition coil.
   • Remove the retaining bolts using the socket set.
   • Carefully pull the ignition coil out.
5. Replace the spark plug:
   • Use a spark plug socket to remove the old spark plug.
   • Inspect the old spark plug for wear or fouling and compare it to the new one.
   • Install the new spark plug to the manufacturer’s specified torque (typically around 13-15 ft-lbs).
6. Reinstall the ignition coil:
   • Place the new ignition coil onto the spark plug.
   • Secure it with retaining bolts and reconnect the electrical connector.

3. Clean or Replace Fuel Injector (if necessary)

1. Remove the fuel injector:
   • Disconnect the fuel injector connector.
   • Remove the fuel rail if necessary to access the fuel injector.
   • Use a socket set to carefully remove the injector from the rail.
2. Inspect and Clean:
   • If the injector is cleanable, use an injector cleaner or ultrasonic cleaner.
   • If it is damaged or clogged, replace it with a new one.
3. Reinstall the fuel injector:
   • Apply a small amount of engine oil to the O-ring of the new injector.
   • Insert the injector into the fuel rail and secure it.