I have noticed a foul smell in my fifth wheel. All sinks have a pee trap, but the shower does not. Is there supposed to be a pee trap installed in the shower?
Have you checked the air admittance valves near the sinks? Sometimes those P traps need to be cleaned out. Take 'em apart and you'll be surprised how much gunk is built up.
I gotta believe there is a trap on your shower drain somewhere. Can you narrow down the area that its coming from. Open a sink cabinet and see if the smell is worse in one of them. My guess is an air admittance valve. Clicky
OK. At least I got a laugh out of 2oldman. No. I am looking at the shower line from the floor to the top of the tank. Absolutely no p trap. Also no sign of any air admittance vales. Guess it is Camping World time.......as much as I detest to deal with them. Thanks for all your input.
How old is the camper? And how long has this happened?
If it's relatively new (within the last 2-3 years), there were a batch of Dometic model 300 toilets that were letting pee get between the base and bowl and would stink up the place.