Car wont start, very intermittent

2001, grand am, 3.4L, auto, remote start

Hey, i've got this problem, every so often my car just refuses to start, it will crank, i can hear the fuel pump, no security light issue (and no indication of passlock issues, with passlock it'll start for about 2 seconds and stall out, but in my situation it never fires), it just refuses to start...

The only way i can get it started is to use "Liquid fire" (ether) i know, bad idea, but when it's your sole transportation to work, you do what you have to do... I spray short bursts of ether in to a hole int he air intake (CAI) and eventually it will start running, i use the ether to keep it running for 10 seconds and then push the gas a bit and it'll keep running on it's own power, so i am certain it's a fuel delivery issue, i just changed the fuel filter, so i know it's not that... it's gotta be the pump, injectors or some electrical computer ish problem... the other thing i noticed (at least for the pas 2 times it's happened) i have had less than 1/4 tank of gas, and the car has sat for 10 hours+, could it be bad gas settling to the top when the car is parked for a while and causing it to not start?... anybody have a similar issue?