my Toyota Corolla E170 (2013-2019) engine is shaking when idle, what could it be

Solution

1. Preparation

• Gather tools and parts for the repair.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Replace Spark Plugs

1. Remove the engine cover (if applicable) using a socket set.
2. Disconnect the ignition coils from the spark plugs.
3. Using a spark plug socket, remove the spark plugs from the engine.
4. Inspect the spark plugs for wear, carbon buildup, or fouling.
5. Replace with new spark plugs that meet OEM specifications (typically NGK or Denso).
6. Torque the new spark plugs to the manufacturer's specifications (usually 13-15 lb-ft).

3. Check and Replace Ignition Coils

1. Reinstall the ignition coils and ensure they are properly connected.
2. If the OBD-II scanner indicated misfire codes, replace faulty ignition coils.
3. Ensure the new coils are seated properly and clip them securely.

4. Clean or Replace the Idle Air Control Valve

1. Locate the IAC valve, usually near the throttle body.
2. Disconnect the electrical connector and remove the mounting screws.
3. Clean the valve using throttle body cleaner, ensuring the passages are clear.
4. If cleaning doesn’t resolve the issue, replace the IAC valve with a new one.

5. Inspect Engine Mounts

1. Visually inspect the engine mounts for cracks, tears, or excessive wear.
2. If any mounts are damaged, replace them with OEM parts following the manufacturer's torque specifications.