Hello again,
Attached is a zipped LabVIEW 2014 project with my second attempt at the Car Wash practice exam. My first attempt was not worthy of consideration. While it had many similarities to the solution from the exam prep kit, my timing vi was unnecessarily complicated, and caused me many problems. Only after completing my first attempt did I look at the solution, and was very impressed with the simple elegance of its timing control. So my second attempt keeps a lot from my first, including the array of states to control the wash sequence as used in the solution, but leans on the solution's timing architecture.
Once again, I appreciate all of the helpful comments I've received on past practice attempts.
Dan