Joepilot

I noticed after about two week my 2003 F-150 V-6 had a low battery and would not crank over. I replaced the battery, same thing won't crank over after about weeks sitting. I discovered there is something pulling about .75 amps with the ignition off. If I put the battery on a trickle charge overnight she would start . If I run the truck every 5 days she is OK. So my charging system is OK. Last time she would not crank over I had a jump and she cranked strong but no light off. I checked the fuel pressure at the rail "0 psi", pump fuse OK, PCM relay OK. The truck has a Ford Anti Theft alarm which I do not activate and there is still .75 amp draw. Does this alarm have a dwell time before she will let the engine start if fhe battery drops below a specific voltage ??. Also what is the normal fuel pressure (psi) pre-start and with the engine running ??? PLEASE HELP !
THANKS