For B4, A3 or early (1998-1999) A4 chassis New Beetle TDI, Golf TDI and Jetta TDI modes that have a oil return line with the banjo-style fitting (with a large bolt) at the block. This adapter is required to use the new-style oil return line. VW has ended the banjo-bolt style fittings on the Oil Return lines themselves. All new VWs come with this adapter in the block from the factory, so, VW removed the banjo style from their supported inventory.
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