how to fix P0301 code in Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, compression tester, multimeter, fuel injector cleaner.
• Safety Warnings: Disconnect the battery before working on electrical systems and allow the engine to cool before proceeding.

2. Replace Spark Plug

1. Remove the engine cover if applicable.
2. Disconnect the ignition coil harness from the spark plug.
3. Unscrew and remove the spark plug using a spark plug socket.
4. Inspect the spark plug for wear; replace it if necessary (use OEM specifications).
5. Apply anti-seize lubricant on the threads of the new spark plug.
6. Install the new spark plug and torque it to the manufacturer’s specifications (typically around 13-16 lb-ft).
7. Reconnect the ignition coil harness.

3. Test and Replace Ignition Coil if Necessary

1. Disconnect the ignition coil from the spark plug.
2. Use a multimeter to test the primary and secondary resistance of the coil according to manufacturer specifications.
3. If the ignition coil is faulty, remove it and install a new one.
4. Torque the ignition coil mounting bolts to the specified torque.

4. Test Fuel Injector

1. Remove the fuel injector connector from cylinder 1.
2. Use a multimeter to check the resistance of the fuel injector against manufacturer specifications.
3. If the injector is faulty, remove it from the fuel rail and replace it with a new one.
4. Reconnect the fuel injector and ensure it is seated properly.

5. Compression Testing

1. Remove the spark plug from cylinder 1.
2. Insert the compression tester into the spark plug hole.
3. Crank the engine for several seconds and note the compression reading.
4. Compare the reading to the manufacturer's specifications; if it is low, further engine diagnostics may be needed.