how to fix P0301 misfire code on my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Remove the engine cover (if applicable) to access the spark plugs.
• Use a socket to remove the spark plug from cylinder 1.
• Inspect the spark plug for signs of wear, oil, or carbon deposits. Replace if necessary.
  • Torque Specification: Tighten the new spark plug to 13 ft-lbs (17.5 Nm).

3. Check and Replace Ignition Coil

• Disconnect the ignition coil connector and unscrew the ignition coil from cylinder 1.
• Inspect the ignition coil for cracks or damage. Replace if defective.
• Install the new ignition coil, ensuring a secure fit and reconnect the electrical connector.

4. Perform Compression Test

• Remove the spark plug from cylinder 1 and insert the compression tester.
• Crank the engine a few times to obtain a compression reading.
• Compare results with manufacturer specifications (typically 180-220 PSI). If low, investigate further for possible valve or head gasket issues.

5. Inspect and Clean Fuel Injector

• Disconnect the fuel injector connector and remove the injector from cylinder 1.
• Inspect the injector for clogs or leaks. Use fuel injector cleaner to flush and clean.
• Reinstall the injector and reconnect the electrical connector.

6. Reassemble and Reconnect Battery

• Reinstall the spark plug, ignition coil, and any removed components.
• Reconnect the negative battery terminal and ensure all connections are secure.