Pontiac Repair: fuel problem, fuel pressure regulator, fuel system cleaners

Question
Hey Todd   I wrote you a couple weeks back about the 95 bonneville having the fuel problem.It starts good when cold but not when its hot unless you let the fuel pressure off then starts good.I tried the fuel system cleaners you mentioned but still no good.I just purchased a fuel pressure tester,With the key on i am only getting 30 psi,running getting 42-44 psi and when you pull the vac hose off the fuel pressure regulator it bumps up to 50 psi. From anything i have read or heard i should be getting 48-55 psi key on and then running it should drop 3-10 psi.I am thinking of changing fuel filter first and if no change i guess probably fuel pump.I just was hoping for your opinion first and what you thought of the readings i was getting and what i heard they should be.      Thank -you     Jeff

Answer
Yes those #'s seem a bit low by about 4-5 Lbs.  I would check to see ewhat happensx to the pressure when you turn the key off and let the car sit. If it bleeds off quicly then either the pressure regulator is leaking or the check valve in leaking inside the pump. That ebing said just being a couple of pounds low shouldn't make it start hard hot. not unless the pressure bleeds off rapidly then you would get a vapor lock issue and that will cause a hard start hot. I think your on the right track but pay attention to the pressure when it sits it shouldn't bleed down with in 20 minutes or so if it does then start looking for a leak.