Fuel pressure dropping while driving and under acceleration to zero at idle runs 4 lb electric Blue

I talked to fuel lab today, They said the chances of that regulator being bad or slim to none. They said that at the regulator inlet where the fuel gauge is should read the pressure of the pump. I have a spring coming that will raise the pressure to 12 to 19 lb. They said if that don't do it then you need to replace the fuel pump. I've been told by several people if you buy one. Holly fuel pump buy two lol