Rough engine start on a 2000 Ford Triton V10

First pumping the pedal will not do anything on a fuel injected engine. The computer makes all the fuel decisions. Second, starting the engine without putting it under load and getting it up to operating temp for at least 15 min is doing way more harm than good and unless you are idling for a really long time you are killing your battery too. Most alternators dont put out much current until they are spinning pretty good. The next time you go to the RV take someone with you and have them listen underneath at the fuel tank as you turn the key on, but dont start the engine. See if they can hear the fuel pump running. If so it should stop in a few seconds, then try to start the engine. If it takes longer to stop pumping get your fuel pressure checked. It may be starting now but if the pump is going there is a good chance that when you hit a hill and step down on the gas the engine will stall from fuel starvation and you will get and engine code, maybe many.