2004-2009 Audi S4 Auxiliary Coolant / Water Pump Hose 8E0819378

The OEM Auxiliary Coolant / Water Pump Hose, part number 8E0819378, is essential for efficient engine cooling in various Audi models, including the S4 and RS4 from 2004 to 2009. This genuine Audi component serves as a return hose, facilitating the circulation of coolant in the engine cooling system. Commonly referred to as the By-Pass Hose or Engine Coolant Overflow Hose, it effectively resolves issues related to coolant leakage and overheating caused by a worn or damaged hose. This part fits snugly in the engine bay, ensuring a reliable connection within the cooling system. Further compatible part numbers include 8E0819378B and 8E0819378C, confirming its authenticity and interchangeability across select Audi models with a 4.2L V8 engine.