I've got an '01 that won't hold fuel pressure at the rail (goes from 35 to zero in about 40 seconds) and as a result I have to crank forever to get it to start, or prime with key turns a couple times but that's a pain. I replaced all 8 fuel injectors with a reconditioned set of delco injectors off Ebay because I had one injector that would act up periodically and hoped that was causing the leak down, but it didn't fix the problem so that's why I'm thinking the backflow is in the tank. I just replaced the fuel pump 6 months ago so I don't want to go in there again just for a check valve and thought about installing one in-line just outside the tank. Any thoughts on going with something like this? http://www.amazon.com/dp/B000YOVLBO/?tag=stangnet-20 If this is a decent solution, anyone know what size line is outside the fuel tank? This product comes in 3/8" and 5/16".