Fueling & Injection - I need your advice on my fuel problem

My dad brought my car to the dealership today and surprisingly got some free advice for what could be wrong with my car. I'm getting 25 psi at the rail and i've already replaced the fuel pump and fuel filter... so we're trying to narrow it down more and finally fix this sun'bitch.

The tech at the dealership said that LS1 f bodies don't come with Fuel pressure regulators, but with a fuel pressure sensor that's attached to the top of the tank. He said if it was malfunctioning, it could limit fuel pressure. He said another possibility could be the fuel tank vent selenoid malfunctioning. do any of you guys know anything about these two devices? any advice is much appreciated.

There is a regulator but it is part of the sending unit in the tank, not external like the other LS1's.

so its in the pump assembly? is it a regulator or a sensor???

You got bad advice for free. Both those parts have absolutely nothing to do with your pressure. there is a regulator as said it is on the pump assembly towards the top. Unfortunately it is not replaceable without a complete assembly.

Nate