1997 Buick LeSabre, 3800 (3.8L)

it starts, idles 1-3 seconds then dies.
if I give it gas, it dies.
New Mass air flow, throttle body, idle air control valve, fuel filter, upstream O2 sensor,& throttle position sensor.
It has stayed running twice since I did all the changing of parts. I might’ve lost my employment as a result of this
PLEASE HELP ME GET THIS TO WORK CONSISTANTLY.

I didn’t see any vacume leaks. Could it be the crankshaft position sensor? Relay for the fuel sending? Something with the fuel pump?
I’m pretty sure that it’* got lots of life left on it; with some love and attention. I do not want her to go to the scrap/salvage yard anytime soon, unless she drives me there to pick-up some spare parts. PLEASE HELP

What does fuel pressure do?
Need to find out what'* missing.

I agree with carfixer007 ^^^^^^^

I'd check fuel pressure first. It sounds like low fuel pressure from this side of the Internet.

Is the check engine light on?

Can you pull codes?

How many miles on it?