fuel pressure dropping over time

The vacuum port will increase fuel pressure when you get on it.
And back off it should go back to set pressure.
If it works like efi regulators.
From what you are describing its a delivery issue. Inspect the rubber hoses,connection at tank, perhaps the hose is collapsing.


?u=https%3A%2F%2Fthumbs.gfycat.com%2FSomberFlippantDevilfish-size_restricted.gif





was able to go for about an hour ride today and it did it again
started out good, but once everything heated up, pressure dropped
at one point, it dropped to zero, and the car died

so i got out, looked around under the hood, like i knew what i was looking for and spotted this

20210623_175449.jpg


the jumper from the new hard line to the pump has just a little kink in it

not a big deal when all is cold, but when it warms up, the line flexes enough for it to collapse


now i got to decide if i want to try to bend it and get it to shoot straight, or find a different way to keep it from doing this