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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool before beginning work.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if necessary.
  2. Disconnect the ignition coil connector.
  3. Remove the ignition coil retaining bolts and lift the coil out.
  4. Remove the spark plug using a spark plug socket and ratchet.
  5. Inspect the spark plug for wear; replace if necessary.
  6. Install the new spark plug, ensuring to torque it to the manufacturer’s specification (typically 13-15 lb-ft).
  7. Reinstall the ignition coil and reconnect the connector.

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. If the spark plug is in good condition, test the ignition coil using a multimeter to check resistance.
  2. If the ignition coil is faulty, remove it from the engine.
  3. Replace with a new ignition coil, ensuring it is properly seated.
  4. Reconnect the ignition coil connector.

4. Check Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Using a noid light or multimeter, check for proper voltage at the injector connector while cranking the engine.
  3. If the injector is not functioning, remove it and replace it with a new one.
  4. Reconnect the fuel injector connector.

5. Verify Engine Compression

• Sub-steps:
  1. If issues persist, perform a compression test on cylinder 1.
  2. If compression is low, further investigation is needed for potential internal engine issues (e.g., valve problems, head gasket failure).