Gaskets are key to a properly running and clean engine. They obviously prevent fluid leaks but they're also critical in keeping air either in or out... Air leaks after the air flow meter, also known as vaccum leaks, can induce lean running conditions, fault codes, and poor running conditions. Other seals and gaskets are designed to keep air in. With the sensitivity of OBD systems, leaks will lead to fault codes very quickly which can be tough to diagnose and prevent you from passing state inspections.
We insist on Original BMW or OEM gaskets whenever possible.
