Just picked up a 94 F150, 4.9l. Ran when I test drove it, wouldn't start when I went to pick it up after I signed for the title. Dragged it home, poked around, found that the fuel pump relay was no good. Replaced the relay, started it up, drove it 30 or 40 miles. Drove back home, went inside to eat dinner, came back out and it won't start again. Brand new relay failed. Any suggestions? Maybe the fuel pump is drawing too hard amperage wise? The guy I got it from said he had the rear tank fuel pump replaced. I'm wondering if this was an attempt to resolve a recurring problem, and maybe the real problem lies elsewhere?