Fuel Pressure Issue on 2003 Silverado 1500 4.3l v6

[Kendoaz]

I picked up my daughters 2003 Chevy Silverado 1500 w/ 4.3L V6 yesterday, and it was running terrible, no power and it felt like it would stall out starting off from a stop. I put my OBD scanner on it and it came up with P0171 and P0174 (running lean on bank 1 and bank 2). I found the Schroeder valve behind the intake manifold and did a fuel pressure check. I came up with 28 psi, and it would hold there for quite some time, so no fuel pressure leaks it appears. I changed the fuel filter, and I still get 28 psi. When I rev the engine it drops maybe 2 psi for a split second but pretty much stays at 28 psi. The strange thing is that it starts just fine, which amazes me being that the truck should be around 55 psi+. It appears to me that the fuel pump is going bad, but I want to make sure before I order a new one. Any ideas on what else I should check? I looked for vacuum leaks, couldn't find any, and I also cleaned the MAF sensor, which didn't change anything. Let me know your thoughts, Thanks.

[rjgti]

looks like it is done, change it

[DrFiero]

Fuel pressure regulator could also be bad (stuck open). Much easier "test fix" than a pump! Cheaper too.