Cranks fine but when I hard accelerate it stalls

This started when I put a tune up on my 97 Tahoe. I had n Noticed that I was getting some hesitation in the Tahoe I just Bought So I bought a complete tune up wires plug wires distributor cap button are filter fuel filter. When installing the distributor cap one of the screws from the old cap Broke off and distributor so I had to take out distributor to remove screw. After installing distributor placing motor at top dead center then setting Cam-retard with Pro scanner was still having problem with hard acceleration. Fuel pressure with switch on is 52 While running it will when accelerating spike up to maybe 58. With pressure gauge hooked up when pressing the pressure release button while running it will kill engine. When restarting you will have to turn key back and fourth at least once to build pressure so engine will start. Scanner does not show misfire. I'm thinking fuel pump. Also looking down into Intake it is very smutty was unsure if this was normal. Fuel pressure regulators like be the first thing to chech other than its under intake plentum is there a way of chech ing without removing Plentum. When driving sometimes you have to just barely press accelerator pedal to keep from cutting out. Sometimes it's better than other times. What do you think. Thanks ahead of time.