I have a motorhome with a 2000 express 3500 van front end. It has an injected 454 with 12000 miles on it. The most recent work performed was an oil change by myself. The other day I started it and it ran for less than 1 minute and died, just shut off. I swapped the fuel relay with the starter relay and it just cranked, no pressure at the fuel filter (I have not checked the shrader valve since I can not get to it). Was told by the dealer it was the fuel pump, so I replaced the whole sending unit/pump combo, still no fuel. Friend checked for power by the tank without any luck. Purchased 2 new relays still nothing. All the fuzes are good. I was also told to check oil sending unit. It was connected and shows just under 40psi when cranking. HELP! I was heading on a trip in 3 days.