2000 225 0x66 erratic fuel pressure

[capehorn]

Hey guys i have a 2000 yamaha 225 ox66 lx225txry. My fuel pressure gets erratic out of no where when I'm at high rpm till it gets so low its shutsdown. it doesn't happen right away maybe 10-15 min into bein on plane and over 3000 rpms. Ran it will the fuel guage while running. I also noticed while running and when the pressure starts to change I could adjust throttle down a bit and it would go back up. It will idle all day on the hose and I can cruise around just not on plane. I've just replaced all three lp pumps, gone thru vst and filter was clean float and needle was ok, checked screen behind pressure regulator it was clean, removed check valve after fuel filter on engine, checked all ground wires and connections also all the plugs nothing was burned and all connections looked good inside the plugs. Was goin to run it tomorrow on spare tank to eliminate onboard fuel issue. This video with the fuel pressure guage for some reason went right to 34 psi and stayed even when unplugged from the shrader valve not sure what happened but as u see in the video guage still works it runs at 70 psi which is 36 -38 psi. So I just used the 34psi it was at as 0. one video is it running smooth and normal the other show the fuel pressure surging
https://www.youtube.com/watch?v=YJSUV8vmr5I