how to fix P0300 code on my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, fuel injector cleaning kit, vacuum gauge.
• Ensure the vehicle is parked on a level surface and the engine is cool. Disconnect the battery before beginning repairs.

2. Spark Plug Inspection and Replacement

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Disconnect the spark plug wires or ignition coils from the spark plugs.
  3. Use a socket wrench to remove the spark plugs.
  4. Inspect each spark plug for wear (gap measurement should be within manufacturer's specifications).
  5. Replace any defective spark plugs with new ones, ensuring they are gapped correctly.
  6. Reinstall the ignition coils or spark plug wires securely.

3. Ignition Coil Testing and Replacement

• Sub-steps:
  1. Remove the ignition coils from their respective cylinders.
  2. Test each coil’s resistance using a multimeter; compare results to manufacturer specifications.
  3. Replace any faulty ignition coils with new ones.
  4. Reinstall the ignition coils securely.

4. Fuel Injector Cleaning and Testing

• Sub-steps:
  1. Remove the fuel injector assembly from the intake manifold.
  2. Use a fuel injector cleaning kit to clean each injector according to the manufacturer’s instructions.
  3. Test each injector's spray pattern before reinstallation.
  4. Reinstall the fuel injectors and ensure they are seated properly.

5. Vacuum Leak Inspection

• Sub-steps:
  1. Visually inspect all vacuum lines for cracks or disconnections.
  2. Use a vacuum gauge to check for proper vacuum levels; a low reading may indicate leaks.
  3. Replace any damaged vacuum hoses.
  4. Ensure all connections are secure.