how to fix the engine misfire in my Toyota RAV4 Fifth Generation (2019-present) with a P0301 code?

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety while working on the electrical components.

2. Replace Spark Plug

• Tools Required: Spark plug socket, torque wrench.
• Remove the ignition coil from cylinder 1 by unscrewing the bolts and gently pulling it out.
• Using a spark plug socket, remove the spark plug from cylinder 1.
• Inspect the old spark plug for wear and replace it with a new spark plug, ensuring it is gapped correctly based on the manufacturer's specifications.
• Torque the spark plug to the manufacturer's specified torque value (typically around 13 lb-ft).

3. Replace Ignition Coil

• Tools Required: Socket set, torque wrench.
• Remove the ignition coil from cylinder 1 if it was previously inspected and found faulty.
• Install the new ignition coil and secure it with the bolts, tightening to the specified torque (typically around 7 lb-ft).

4. Check and Clean Fuel Injector

• Tools Required: Fuel injector cleaning kit (if required), socket set.
• Remove the fuel injector from cylinder 1 using the appropriate tools.
• Inspect the injector for clogging and clean it using a fuel injector cleaning kit or replace it if necessary.
• Reinstall the fuel injector and ensure all connections are secure.

5. Compression Test

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 1 and install the compression tester.
• Crank the engine a few times and record the compression reading. Compare it to the manufacturer’s specifications (typically around 180-200 psi).
• If the compression is low, further investigation is needed to identify the cause (e.g., valve issues, head gasket failure).