Genuine OEM Audi Knock Deflector, part number 07L905377E. This component is a knock sensor that detects vibrations caused by engine detonation or 'knocking'. Upon detecting such vibrations, it sends an electrical signal to the engine control unit (ECU). The ECU then adjusts ignition timing to prevent engine damage and maintain optimal performance. This part is typically mounted directly to the engine block. It is a critical sensor for engine management. Genuine OEM knock sensors are calibrated to precise specifications to ensure accurate detection of abnormal combustion events, protecting the engine and maximizing efficiency.