If there was a leak on the water seperater valve would that cause the fuel pressure to maybe drop? I did notice mine was leaking and went to order one but there is 936 on back order in the local dodge store...

Does anyone know at what pressure does a FASS 150 run at without a regulator?

My heavy duty series 150 has 23-24 at idle, and 21-22 at WOT, at the IP. I also have the factory fuel filter in the fuel system.

where is your fuel pressure gauge at? at the lift pump or the injection pump or the fuel filter?

It's right on the banjo bolt for the VP44 supply.

Suggest you get rid of the banjo bolts! All of them!!!!!!

BTW - if you get the Vulcan line kit to eliminate the banjo bolts, you can get a fitting that attaches to your VP44 pump that has a tap-off to measure your fuel pressure - AS IT GOES INTO THE VP44.

It is far better to measure the pressure at the place it really counts!!

(I would think that if you keep pressure to the VP44 - measured at the VP44 - above 5 psi - you would be in much better shape than if you were measuring 5 psi at the fuel filter!! If 5 psi at the fuel filter, what is the pressure at the VP44??)