how to fix a check engine light for P0301 on my Toyota RAV4 XA40 (2013-2018)

Solution

1. Preparation

• Gather tools and parts needed.
• Disconnect the negative battery terminal.
• Allow the engine to cool before starting work.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover (if applicable) using a socket set.
  2. Disconnect the ignition coil connector for cylinder 1.
  3. Unbolt the ignition coil and remove it from the spark plug.
  4. Remove the spark plug using a spark plug socket.
  5. Inspect the spark plug for wear; replace it if necessary (gapped at 0.043 inches).
  6. Install the new spark plug and torque it to 13 ft-lbs (17.5 Nm).
  7. Reinstall the ignition coil and reconnect the connector.

3. Test Ignition Coil

• Sub-steps:
  1. Use a multimeter to measure the resistance of the ignition coil. Ensure it reads between 0.4 to 0.6 ohms for primary and 10k to 15k ohms for secondary windings.
  2. If outside the range, replace the ignition coil.
  3. Reinstall the ignition coil if it passes the test.

4. Check Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Test the injector with a multimeter; it should show resistance between 12-16 ohms.
  3. If the injector is faulty, replace it.
  4. Reconnect the fuel injector.

5. Vacuum Leak Inspection

• Sub-steps:
  1. Inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  2. Use a smoke machine or carb cleaner while monitoring RPMs; a change in idle indicates a leak.
  3. Repair or replace any damaged hoses.

6. Compression Test

• Sub-steps:
  1. Remove all spark plugs for easier cranking.
  2. Attach the compression gauge to the spark plug hole for cylinder 1.
  3. Crank the engine several times and record the reading; it should be within 130-190 psi.
  4. If compression is low, further inspection of the valve seats and piston rings is necessary.