Dj Cutler

The fuel pump puts out a steady 58psi and only drops maybe 2psi when you step on it. But after driving around for an hour or so, I start to lose power then eventually its hard to take off from a stop without it dying. But starts right back up. The fuel pressure while idling when its acting up goes from 58 as low as 7 psi then kicks back up to 58 psi. The pump itself was bought back in January 2013, and it only has maybe 3000 miles on it since then. It sat when I moved to a different state. Had stable put in and was ran every month.. Is the pump taking a crap on me again, or is it just another issue that might be causing this? I have never seen any pumps act this way before.