I found a vacuum hose that runs from the drivers side to passenger side in the back of the engine was disconnected in my truck. On the drivers side it is hooked up to s "speed control" unit just inside of the fender near the windshield and it is disconnected on the passenger side. I have looked through all of the vacuum hose diagrams I can find but I don't see it listed anywhere. Anybody know where this hose is supposed to hook up?