What should I do if the engine vibration of Buick New LaCrosse is abnormal?

Hello: According to the phenomenon you described, the engine is shaking and abnormal. First, check the working conditions of all parts of the ignition system, and check the spark plugs, high-voltage leads, ignition coils, etc. Poor operation of these parts will lead to engine jitter, poor acceleration or power reduction. Secondly, check the carbon deposit on the electronic throttle body. There will be more carbon deposition when the vehicle travels 14000 km. You can clean up the carbon deposit and observe it during the trial operation.