rated ///M· Registered
2002 BMW M5
Take off the manifold and check all your vacuum lines under there and the plastic L fitting (located between 2 vacuum lines). I would also get a new intake manifold gasket and replace it while you have everything apart. Take off the ICV and twist it side to side, the metal flap inside there should move freely, if it doesn't use some carb cleaner and spray it in there while moving the flap up and down.