Have a terrible gaseous smell that seemed was being drawn in through air conditioner (thought from sewer). After reading from many sites I believe this is not possible. My Cameo Carriage is equipped with the 360 shark fin and I have checked all sink traps and they have water holding in them. The smell is about to make me sick. After the smell began I shut off a/c for 2 hours, opened vents and window and have tried to air out to localize the smell but am unable to locate it's origin. Toilet smells fine, sinks smell fine do not know where this is coming from. My husband is at work and not allowed to use cell phone so, here's the stupid "girl" question. Can this noxious smell like none other I have ever smelled be coming from my washing machine drain if my gray water is being left open? If not, any other suggestions and diagrams..lol..would be helpful.