The contact owns a 2011 BMW 328XI. The contact stated that while driving at unknown speeds, an odor appeared from the exhaust pipe and under the hood where the engine was located. The contact mentioned that every year the oil was changed at an independent mechanic where it was diagnosed and determined that the valve gasket failed and needed to be replaced. The vehicle was not repaired. The failure recurred. The contact feels unsafe driving the vehicle. The manufacturer was notified of the failure and provided the contact with a case number. The dealer was contacted and confirm that no recalls under the VIN. The contact mentioned NHTSA Campaign Number: 17V683000 (ENGINE AND ENGINE COOLING) as a possible solution to the failure however the VIN was not included. The failure mileage was approximate 52,202