wash and wax shampoo does it cause build up??

[Calendyr]

Not a big fan of these type of products either. As for build-ups, I would really doubt it. They most likely use carnauba wax in their formulation, and that stuff evaporates rather quickly when the sun is beating down on your paint. Also the quantity of wax in the shampoo is very likely very small. I would not worry about it.