We had a reoccurring smell in our 5th wheel for over a year. It would come and go. We tried everything. Finally out of desperation we removed a piece of paneling right next to the fusebox and saw there was a small leak where the toilet came through the floor. It would leak just a small amount at a time, so when we stayed in one place for awhile, the water would accumulate and smell. We discovered the floor was also soft around the toilet. We had to add a new piece of plywood and all new fittings, flanges and seals. Now everything is dry and the smell is gone. We were about ready to trade it in.
