Low fuel pressure

[Nilao]

When mine sucked the passenger tank dry it was trash that got sucked up into the suction line in the tank. I unhooked the line from the diverted valve and blew through it and a piece of orange rtv silicone came out. Being there is no rtv sealant on my tank all I can presume is someone dropped it in there.

That could be your issue or the vent is plugged, the stand pipe has a crack in it at 1/4 tank level (not likely). Yes the diverted valve could also be bad but on my prostar it's equalized by pressure in the tank. The diverted valve on mine is nothing but a restrictor as the return fuel has to go through small metering holes to help keep the pressure to each tank equal.