how to fix P0300 misfire code in Toyota Corolla E170 (2013-2019)

Solution

1. Preparation

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

2. Replace Spark Plugs

• Sub-steps:
  1. Remove the ignition coil assembly using a socket set.
  2. Remove the old spark plugs with a spark plug socket.
  3. Inspect the cylinder head for debris and clean if necessary.
  4. Install new spark plugs, ensuring the correct gap is set (typically 0.043 inches for this model).
  5. Reinstall the ignition coil assembly and torque to manufacturer specifications (usually around 7.2 ft-lbs).

3. Test and Replace Ignition Coils (if necessary)

• Sub-steps:
  1. Use a multimeter to test each ignition coil's primary and secondary resistance.
  2. Replace any coils that do not meet specifications.
  3. Reinstall the coil(s) and connect wiring harness securely.

4. Inspect and Clean Fuel Injectors

• Sub-steps:
  1. Remove the fuel rail assembly to access the injectors.
  2. Clean the injectors using a specialized cleaning kit or replace them if clogged.
  3. Reinstall the fuel rail and tighten to specifications.

5. Vacuum Line Inspection

• Sub-steps:
  1. Inspect all visible vacuum lines for cracks or disconnections.
  2. Replace any damaged lines with OEM specifications.
  3. Ensure all connections are tight and secure.