What causes the Audi Q5 to shake?

[McSilas]

The most common cause of idle shaking is a dirty or faulty throttle body. The primary reason for a dirty throttle body is the buildup of carbon deposits at the junction between the throttle valve plate shaft and the throttle body, which results in imprecise throttle opening and consequently causes idle shaking. Additional information is as follows: 1. Clean the throttle body: If the shaking stops after cleaning, it indicates the issue was caused by a dirty throttle body. If the shaking persists after cleaning, the throttle body assembly may be damaged and require replacement. Since modern vehicles use electronic throttle bodies, it is necessary to recalibrate the idle speed after cleaning the throttle. 2. Poor fuel quality: This can lead to inadequate atomization of the fuel injectors, causing incomplete combustion of the air-fuel mixture in the cylinders, which also results in idle shaking. It is recommended to use higher-grade gasoline after finishing the current tank and perform a fuel system cleaning. 3. Abnormal spark plugs: If spark plugs fail to ignite, it can cause one or more cylinders to stop working, leading to idle shaking. Inspect the spark plugs—if there are cracks in the ceramic part, also check whether the ignition module is functioning properly.