2000 Venture engine trouble

Hey folks, I have a 2000 venture with 175,000 miles that is hard to start at times. If you start it everyday it usually starts normally. If it sets for any period of time beyond that it is really hard at starting, it backfires, acts like it wants to start. Once it is started it runs fantastic. the only code i have is a p0449 which has been on for years and has had no effect on it. I have 50 psi fuel pressure. I hear the fuel pump shutting off within a few seconds after the key is turned to on. Any help will be appreciated as I do most of my own maintenance and am curious if ive missed something simple. Thanks to all.

How fast does the fuel pressure drain off, after the pump stops? Fuel pressure spec for key on engine off, 52--59psi.

Charcoal cannister is in the rear of the vehicle, I had a small dog chew the wires on mine to cause the codes to come up.

Check Fuel pressure regulator, pull the vac line off and see if there is any raw fuel in the line. Does the pressure rise whent the line is pulled?

Spec on my 97 is like 41-47, I got some contradictory results on a 2000 when looking it up, but it should have a different style injector and I assume it may have a higher pressure spec because of the style......

Will it start better with a quick shot of starting fluid or carb cleaner? Start better with accelrator pedal on floor (WOT)?

Thanks for all the good info everyone. Ill try a shot of starting fluid and see what happens. I did hook the fuel pressure guage up again and with the key on the pressure is about 58 ,after starting the pressure is about 52-53 while reving the engine the pressure jumps to 58 then holding the accel it levels to 50-51. shut it off the pressure goes back to 58. There is no raw fuel in the regulator hose.

The pressure bleeds down very slowly per the guage.