I recently let a "quikie" car wash clean my 03 Tahoe. I noticed after a couple of days that the window trim on the passenger window was stained by some chemical they used. It is a stain as if an oily substance had been applied to it. This is the hard rubber on the bottom of the window. What is recommended to remove the stain? I have washed the car twice since then and the stain is still there!