Intermittent starting

I have a 99 2dr 4x4 that starts fine most of the time. Once a month or so the fuel pump won't come on. I've installed a good bosch pump, new filter , and a new relay. All to no avail. I recently found a bad schrader valve on the line and changed it, but the same problem happened again today. The relay is clicking but no obvious pump noise. My ? is I've heard of an electrical problem that may cause this. ie sensor, ignition, or computer. I'll through money at it, just tired of being w/o wheels for days at a time!:mad2:

go to www.carterfueldelivery.com