how to fix the P0301 misfire code on my Toyota RAV4 XA50 (2019-2024)

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, compression tester, fuel injector cleaning kit.
• Disconnect the negative battery terminal to ensure safety while working on the vehicle.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if necessary to access the ignition components.
  2. Disconnect the ignition coil connector from the cylinder 1 ignition coil.
  3. Unbolt and remove the ignition coil from cylinder 1.
  4. Remove the spark plug using a spark plug socket and ratchet.
  5. Inspect the spark plug for wear, carbon deposits, or damage; replace if necessary.
  6. Install the new spark plug to the manufacturer’s specified torque (typically around 13-16 lb-ft).
  7. Reinstall the ignition coil and reconnect the connector.

3. Test and Clean Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Use a multimeter to test the injector resistance (should typically be around 12-16 ohms).
  3. If the injector is faulty, replace it with a new one.
  4. If operational, clean the injector using a fuel injector cleaning kit according to the manufacturer's instructions.
  5. Reconnect the fuel injector connector.

4. Perform Compression Test

• Sub-steps:
  1. Remove the spark plug from cylinder 1.
  2. Insert the compression tester into the spark plug hole.
  3. Crank the engine for a few seconds and observe the compression reading.
  4. If compression is below the manufacturer’s specification (usually around 180-210 psi), further investigation for internal engine issues is required.