91 S-10 starting problems

I have a 91 S-10 with a 2.8 I went to leave for work yesterday and I started my truck, but I forgot something in the house ran back in left the truck running when I came back out It was sputtering and cut off. I have checked for fire it is firing. The truck has a new fuel pump and filter. any ideas.

Make sure it is getting good hot blue spark to more than one spark plug.
Carb or TBI fuel injection?
If TBI fuel injection.
Is the fuel pump running the 2 second key on engine prime cycle.
and pumping right pressure?
Also check all fuses some engine running stuff is fused.
Has it got plenty of fuel in tank?
MT