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

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, fuel injector tester, compression tester, vacuum gauge.
• Ensure the vehicle is parked on a level surface, with the engine off and cool.

2. Replace Spark Plug

1. Remove the engine cover if applicable.
2. Disconnect the ignition coil connector and remove the ignition coil.
3. Use a spark plug socket to remove the spark plug from cylinder 1.
4. Inspect the new spark plug against the manufacturer’s specifications for gap and type.
5. Install the new spark plug, ensuring it is torqued to 13 lb-ft (17.5 Nm).
6. Reinstall the ignition coil and reconnect the connector.

3. Replace Ignition Coil (if necessary)

1. If the ignition coil was faulty, remove it from cylinder 1.
2. Install the new ignition coil and ensure it is seated properly.
3. Reconnect the ignition coil connector.

4. Replace Fuel Injector (if necessary)

1. Remove the fuel rail according to the manufacturer's specifications.
2. Disconnect the fuel injector connector and remove the old fuel injector.
3. Install the new fuel injector, ensuring proper alignment and sealing.
4. Reattach the fuel rail and reconnect all necessary connections.

5. Perform Compression Test (if necessary)

1. Remove the spark plug from cylinder 1 again.
2. Insert the compression tester into the spark plug hole and crank the engine.
3. Compare the reading to the manufacturer's specifications; if it is low, further investigation is required.

6. Test for Vacuum Leaks

1. With the engine running, use a vacuum gauge to check for proper readings.
2. Inspect all vacuum lines and the intake manifold for any signs of leaks.