I would just like to put this out there for anyone experiencing running problems with cars that have Rochester Valves. I've experienced various running problems with both my 95 6.0 and my 96 4.0 that were solved when I opened the respective Rochester Valves and cleaned them out. They are no longer available new, and similar looking valves are not the same on the interior and generally will not work. The valves are plastic and will just snap open and snap closed. There is a diaphram and a spring inside so be careful when opening. Make sure to clean the openings and make sure it goes back together oriented as it was originally. These valves are now very old and clogged with debris. If you experience wooshing when you open the gas cap or have running problems that you can't solve, try cleaning the Rochester Valve.