This is the intake manifold end plate seal gasket. GM labeled it as Intercooler End Plate Seal 12584355 It is located on the intake manifold on the end plate where the lamonova cores are located. GM part #12584355 which is now discontinued.
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2010 10 Audi A6 Quattro 3.0T SUPERCHARGER INTAKE MANIFOLD,THROTTLE BODY..
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