how to diagnose the engine misfire in my Toyota Highlander Third Generation (2014-2019)

Solution

1. Preparation

• Gather required tools and parts.
• Disconnect the battery to ensure safety.
• Allow the engine to cool before starting work.

2. Replace Spark Plugs

1. Remove the engine cover (if applicable) using a socket set.
2. Disconnect spark plug wires or ignition coil connectors.
3. Use a spark plug socket to remove the old spark plugs.
4. Install new spark plugs (ensure they are properly gapped as per manufacturer specifications).
5. Reconnect the spark plug wires or ignition coils.

3. Inspect and Replace Ignition Coils

1. Remove the ignition coils by unscrewing the retaining bolts.
2. Inspect the coils for damage or corrosion.
3. Replace any faulty ignition coils with new ones.
4. Reinstall coils and reconnect any electrical connectors.

4. Check and Clean Fuel Injectors

1. Use a fuel injector cleaning kit or professional service to clean injectors.
2. If injector replacement is necessary, remove the fuel rail and disconnect fuel lines carefully.
3. Replace faulty injectors with new ones, ensuring they are properly seated.

5. Inspect and Repair Vacuum Leaks

1. Visually inspect all vacuum lines for cracks or disconnections.
2. Use a smoke machine or carb cleaner to identify leaks while the engine is running.
3. Repair or replace any damaged lines or gaskets.