how to fix P0301 code on Toyota Corolla E140 (2006-2013)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle's battery to ensure safety while working on electrical components.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, spark plug socket, torque wrench.
• Remove the ignition coil from Cylinder 1 by unscrewing its mounting bolts and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket.
• Inspect the spark plug for wear; replace if necessary.
• Install the new spark plug by hand to avoid cross-threading, then torque to manufacturer specifications (typically 13-16 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Test and Replace Ignition Coil (if necessary)

• Tools Required: Multimeter.
• Use a multimeter to test the ignition coil's primary and secondary resistance.
• If the readings are outside the manufacturer's specifications, replace the ignition coil.
• Reinstall the new ignition coil, ensuring it is securely fastened.

4. Check and Clean Fuel Injector

• Tools Required: Fuel injector cleaner or replacement injector.
• If the fuel injector is suspected to be clogged, use a fuel injector cleaner or replace it with a new one.
• To replace, disconnect the fuel rail and remove the injector from its socket, then install the new injector.

5. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use the OBD-II scanner to clear the P0301 code from the vehicle's computer.