Genuine OEM Audi Engine Oil Check Valve, part number 079103765E. This critical component is designed to regulate the one-way flow of engine oil within the lubrication system, preventing backflow and ensuring oil is present where needed upon startup. It is typically installed in an oil passage within the engine. Constructed from durable plastic with a sealing O-ring, it maintains oil pressure and flow integrity. Using a genuine OEM check valve guarantees precise calibration, correct material composition, and reliable operation, which is vital for the long-term health and performance of the engine.