what causes rough idling in my Toyota Highlander XU70 (2020-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on the engine.

2. Inspect and Replace Spark Plugs

1. Remove the engine cover using a socket set.
2. Disconnect the ignition coils by unplugging the electrical connectors.
3. Unscrew and remove the spark plug using a spark plug socket.
4. Inspect the spark plugs for wear; replace if necessary with OEM specifications.
5. Install new spark plugs by hand-tightening and then torqueing to manufacturer specifications (typically 13-15 ft-lbs).
6. Reconnect the ignition coils and replace the engine cover.

3. Clean or Replace Air Filter

1. Locate the air intake box and remove the clips or screws securing it.
2. Take out the air filter and inspect it for dirt and debris.
3. If dirty, clean the filter if reusable or replace it with a new one.
4. Reassemble the air intake box securely.

4. Check and Repair Vacuum Leaks

1. Visually inspect all vacuum hoses for cracks or disconnections.
2. If any hoses are damaged, replace them with OEM parts.
3. Use a smoke machine or carburetor cleaner to identify any hidden leaks.

5. Test and Replace Fuel Pump (if necessary)

1. If fuel pressure is low, remove the fuel pump access cover (if applicable).
2. Disconnect the fuel lines carefully to avoid spills.
3. Replace the fuel pump with a new unit, ensuring all connections are secure.
4. Reconnect the battery and test the vehicle.