Hey Duck,
Most likely a fuel pump issue. Read my post over . Titled "fuel pump and info", the end is the fuel pump figures etc. It will be hard to catch at first,pressure will fluctuate also based on fuel tank level,load, duration of run time. In the begining the pump can tes out okay for a while. Mine was acting up intermitantly for 4 mos and couldn't catch it umtil hot weather hit. I still had to run if for over and hour till she tanked. The the longer I ran it the worse it got. First psi dropped to 22lbs, thaT LET ME HAVE 4 GRAND WOT. The it would dropp to 12lbs at wot. Note the pump did not read a fail psi until I was into the pedal a fair amount or wide open. The hotter it got the longer it ran the more psi dropped....only under load of acceleration. Cruising the pump maintained it's psi. See my other thread for a bit more info on this. Ps go drive the car with a pressure guage duct taped up right on the wiper arm. on the windsheild you will get wrong readings due to angle of view on the guage....now go drive around...soon as you get enough time on it the pump will heat up and then when you punch it you will see the pressure drop. note car runs stronger after a break due to pump rsting and cooling.
Sorry for the :q:q:q:q a$$ gramar in a rush and not going back to do the typos lol.