What causes the body shaking of Audi A4?

[DelJanelle]

Here are the possible reasons for the shaking: 1. Excessive carbon deposits - Severe carbon buildup in the engine cylinders can lead to spark plug blockage and valve clogging, directly causing vehicle shaking during idling. If the car's acceleration performance has significantly deteriorated with persistent shaking, consider an engine cylinder cleaning. 2. Fuel supply system failure - Unstable fuel pressure may cause inconsistent mixture concentration, resulting not only in shaking but also unstable idling. First consider replacing the fuel filter, as prolonged use may clog the filter element. Then check the fuel pressure bypassing the filter - if abnormal, it might indicate a fuel pump issue. 3. Worn engine mounts - This is a very common cause of shaking. If the engine vibration worsens without corresponding power loss, consider checking the engine mounts. 4. Misfiring cylinders - This is the most common cause of engine shaking (perhaps even the most frequent). The problem lies in the engine ignition coils or spark plugs. If the ignition coil malfunctions or spark plugs fail to fire for any reason, the vehicle will experience shaking.