how to fix my Toyota RAV4 XA40 (2013-2018) with a P0301 misfire code

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the battery to prevent any electrical hazards.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1:
  • Unscrew the retaining bolts (use a socket set).
  • Gently pull the coil off the spark plug.
• Remove the spark plug:
  • Use a spark plug socket and ratchet to unscrew the spark plug.
• Inspect the spark plug for wear or carbon buildup; replace if necessary.
• Install a new spark plug:
  • Torque to manufacturer specifications (usually around 13-15 lb-ft).
• Reinstall the ignition coil and secure it with bolts.

3. Check and Replace Ignition Coil (if necessary)

• If the spark plug appears in good condition, test the ignition coil for proper resistance using a multimeter:
  • Compare readings with manufacturer specifications.
• If the coil is faulty, replace it with a new one:
  • Install the new ignition coil and reconnect the electrical connector.

4. Clean or Replace Fuel Injector

• If the spark plug and ignition coil are functioning properly, check the fuel injector:
  • Remove the fuel injector harness and unscrew the injector from the rail.
• Clean the injector using a fuel injector cleaning kit or replace it if clogged.
• Reinstall the cleaned or new injector securely.

5. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use the OBD-II scanner to clear the P0301 code and any other stored codes.