Moreover, the exhaust manifold gasket in your Audi A3 is generally used as a seal between the engine cylinders and the exhaust system. In general, the exhaust manifold leak is the common one that indicates something severe in your vehicle. Neglecting the issues for longer may damage the engine and cause some healthy hazards by letting the toxic fumes into the cabin. The following slides define the symptoms of exhaust manifold leaks in Audi A3.