What Causes Intermittent Idle Vibration in the Buick Excelle?

[LaIan]

This is due to a dirty throttle body, which requires cleaning. Here are the specific reasons: Dirty throttle body: The main reason for a dirty throttle body is carbon buildup at the junction between the throttle valve plate shaft and the throttle body, resulting in imprecise throttle opening and causing idle vibration. Poor fuel quality: Low-quality gasoline leads to poor atomization in the fuel injectors, causing incomplete combustion of the air-fuel mixture in the cylinders, which also results in idle vibration. It is recommended to use higher-octane gasoline after consuming the current tank and perform a fuel system cleaning. Faulty spark plugs: If spark plugs fail to ignite, causing one or more cylinders to misfire, this will also lead to idle vibration. Inspect the spark plugs; if cracks are found on the ceramic parts, also check whether the ignition module is functioning properly.