S10 Stall

I have a 2000 S10 with the 4.3L V6 and twice in the last month I have gone to start it and as soon as it turns over, it dies. It takes about 3 to 4 tries before it keeps running but the idle is rough and choppy until I give it some gas. The first time this happened the truck had sat for a couple days without being started but the second time it happened I drove it to the store and when I got in to leave the store it did the same thing. I took it in and had it checked but they said it may be some loose wiring and my friend said it may be the idle sensor. I have no clue what it is so I need some help.

Was the fuel pressure and a code check run on it?
Any check engine or security lights staying on?
Any add on remote start or anti theft?
How many miles on the tune up end?

Hard to start cold check that fuel pressure.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.
Post back fuel pressure readings.