The hiss caused by removing a gas cap has been eliminated because of a vacuum cut valve that routes vapors to the engine instead of the gas tank. A supplier of these valves, Japanese-owned Piolax Corp., had been shipping these valves from Japan to its plant in Canton, GA, but this was getting costly and Piolax considered moving production to the United States.
In order to move production, the quality control testing system had to be updated to include documentation of each valve's compliance with buyer specifications for actuating pressures, flow and leakage rates. "We could not bring the valve manufacturing responsibility to Canton until we could demonstrate our ability to fulfill valve function tests reliably, and at volume production rates," said Kevin Holcomb, plant engineering director for Piolax.