how to fix a P0301 code in my Toyota RAV4 XA40 (2013-2018)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plug and Ignition Coil

• Tools Required: Socket set, torque wrench, spark plug socket, ratchet, dielectric grease.
• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Disconnect the electrical connector from the ignition coil of cylinder 1.
  3. Remove the ignition coil bolt and carefully extract the coil from the spark plug well.
  4. Use a spark plug socket to remove the old spark plug.
  5. Inspect the spark plug for damage. If necessary, replace it with a new one, ensuring to gap it according to manufacturer specifications (typically 0.043 inches).
  6. Apply a small amount of dielectric grease to the ignition coil boot and install the new ignition coil.
  7. Reattach the ignition coil bolt and the electrical connector.

3. Check Fuel Injector

• Tools Required: Noid light or multimeter.
• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Connect the noid light to the injector connector and crank the engine; the light should flash. If it does not, the injector may be faulty or there may be an electrical issue.
  3. If the injector is faulty, replace it with a new one, ensuring proper installation and connection.

4. Reassemble and Final Checks

• Reinstall any components that were removed, including the engine cover.
• Reconnect the negative battery terminal.
• Clear the P0301 code from the ECU using the OBD-II scanner.