The soap they use inside the carwash is blue and purple, and it smells like bubblegum.
(In desperation, I took my car through the carwash for perhaps only the second time in my life, but it didn't do so hot a job after all, even though the car looks kinda sorta decent now. I definitely could have done a better job myself, if I weren't lacking in time. So the carwash request is still on. You'd get paid in ice cream, California sunshine, and blue fuzzy socks.)