Fuel Pressure Regulator?
 

97 Chev K1500 w/5.7. Truck drives fine an normal pace, but if I floor it, it seems like it's not getting enough fuel. More of a hesitation/missing than a bogging feeling. When I check fuel pressure I get 60ish when I turn the key on, but it only stays there for a second and starts dropping till it hits about 10 PSI. If the truck is running the fuel pressure stays at 55ish and doesn't move if I rev the engine. I do have codes for the EGR pintle and the 2 downstream O2 sensors, but that wouldn't explain the fuel pressure problem. I'm taking a guess at the fuel pressure regulator, but don't want to rip anything apart if you guys have something else I should check first.
TIA!
Scooter

Can you slowly close off the return line with the engine running and a pressure gauge hooked up? If so does the pressure increase when pinching off the return line? If it does increase then the pressure regulator is probably defective. If not the fuel pump should be the problem.

Remember this, you can have pressure but not enough volume and have the problem you describe.