VAG 059121131S Coolant Connection Flange

The 059121131S is a genuine Volkswagen Group (VAG) coolant connection flange designed for the 3.0 TDI V6 engine family. It serves as a critical junction in the engine cooling circuit, connecting coolant hoses to the engine block or cylinder head. Constructed from high-temperature resistant engineering plastic, the flange features a 20 mm outer diameter connection port and includes a sealing gasket to prevent coolant leakage. The component is known to be a maintenance item due to plastic fatigue from thermal cycling. It supersedes part number 059121131B. Direct OEM replacement ensures exact fitment and restores cooling system reliability.