An exhaust control system for a power source is disclosed. The exhaust system has an air induction system, an exhaust system, and a recirculation system. The recirculation system is configured to direct at least a portion of an exhaust flow from the exhaust system to the air induction system. The exhaust control system also has a sensor configured to detect the presence of sulfur, and a controller in communication with the sensor. The controller is configured to modify operation of the recirculation system in response to the detected presence of sulfur.