Cold Start Issue....ideas?

[Coley]

Ok...I'm just starting to get the truck ready for summer with it having been in storage and I'm noticing something.
This started late in the fall...as follows:
Pump the gas and truck pretty much immediately fires...then immediately dies as soon as the key is released.
It seems to be getting enough fuel...the choke is opening correctly.
Is this something in the ignition switch? or coil?...or wiring? ...or electrical at all?

So, I thought I read something here about this maybe being a faulty ignition switch or???....so when I tried it again...i left the key (and starter) spinning for an extra 1/2 second and it fired right up. (naturally I won't make a habit of this...lol)
Once warm, it does start without issue and it runs great the rest of the time....but the initial cold start incident of it 'snapping off' is a little confusing....because it does want to start and it does fire...it just quits as fast for some reason.
I'm not too worried about it and I will recheck the choke business....but I just want to make sure that there is nothing else to be looking or checking for.

Any thought or input on this is welcome.
Thanks!
Coley