I got it running today. Ran it directly off a battery sliced into the lines going to the pump from by the door. Ran fine psi at 39.5 which is where it should be. Also had 12 volts at the connection. I will try adding a additional ground to it, if that does not work will add a inline fuse and run in directly to a car battery. For as much as I will be using it that will be good enough. It adds character to the car. Something Red Green would have done.

Red green would definitely recommend using duct tape in the wiring lol.
We prefer new wires w/ solder heat shrink tubing & electrical tape right ?

Secure the harness well.

“If the women don't find you handsome, they should at least find you handy.”

If it were me..... assuming that ground actually is the issue, I would be tempted to just whack a self tapper screw with a ring terminal on it and use that as the ground and just call it good.

Plan B would involve just confirming you have the correct voltage output at the fuel pump relay output, and just splicing off of that lead for your home run, and grounding somewhere on your own.

The less I have to get under the hood to hook up/disconnect a wire when I want to drive the car, the better. Plus, there could be safety concerns too in the event of an incident...

I have to open the hood to disconnect the battery anyways because it will kill the battery if it sits for to long. Considering I drive the car a few times a year its not a big deal.

I might just use a 2nd car battery with a inline fuse or some kind of power supply to the fuel pump instead of running it all the way to the hood.

I did try a couple things with the ground. I tried tapping into the current ground and adding a ground wire to a good spot clean metal spot on the door. Voltage was still 8.20 volts. Tried just grounding out the wire form the pump to the door. Still 8.20 volts. Could it be the power wire is exposed somewhere?

I thought it was working but it still does drop pressure after a while. Just starts higher close to 40. Before it started around 33. Same deal on 3 different pumps. One new thing its doing is it will not shut off with the key after its been running for a while. When you first start it up the key shuts the car off, after it does nothing. I shut the pump off and the car shuts of immediately that exact second. But then the pressure is dropped a lot to say 20 or less.

Friend suggested checking the ignition relay.

You need to fix the wiring.

Agreed, if the fuel pump was not severed from the factory harness when you hooked it direct, it may be back feeding power.

The key now shuts if off all the time. It was because from the power wire from the fuel pump is one wire that splits into 3 wires. And 2 of the wires were still hooked up but are no longer.

I do not understand what back feeding power is? If its directly getting juice from a external source. Directly to a separate car 12v battery.

Please give me a list of everything that could cause fuel pressure to drop over a short period of time. I do find it interesting that since I ran it on a separate source it starts at 38 psi vs the 33 psi it was at.

3 different pumps have had the same outcome. A new regulator was installed. The lines are not leaking. There is plenty of gas. I do not understand how a pump can be forced to slow its pressure. I would think it would be a constant and would have to stay at a set spot.

The regulator does not have fuel coming out and when the vacuum line is removed the psi jumps up about 10.

6 Causes of Low Fuel pressure

1. Clogged Fuel filter BRAND NEW
2. Bad fuel pump BRAND NEW AND OTHER PUMPS TRIED
3. Bad fuel pressure regulator PUT ON A BRAND NEW ONE
4. Stuck Fuel injector ????
5. Bad fuel pipe line NO BECAUSE PSI AT THE OUTPORT OF THE FILTER ALSO DROPS. ABOUT 3 FEET OF GOOD FUEL HOSE GOING TO THE FILTER. SO A BAD LINE DOWN THE SYSTEM WOULD STILL HAVE GOOD PSI AT THAT SPOT. I ASSUME.
6. Fuel pressure sensor N/A