98 Dodge Ram 1500 problems starting and staying running

I have a 98 Dodge Ram 1500 5.2L v8 2wd
automatic pickup truck. The problem started out a
few days ago. It would crank and go a few miles
then shut down. I went to the store and when
pulling out of the parking lot it died. I went back to
pick it up the following day it crunk up an I was able
to get it home but I couldn't get it over 25 mph
without it trying to stall. I left it idling in the driveway
when I got it home for a few minutes and when I
gave it a little gas after sitting idling it died instantly.
I have since crunk it once and this morning tried to
crank it again but no start. It will turn over but not
start. The fuel pump cuts on and it gets spark on all
plugs and the coil. I'm not sure of the fuel pressure
or voltage output but it does get gas to the engine
and spark to the plugs. When it was idling it ran
pretty normal but seemed to be running a little Rich.
I have replaced the coil pack and the crankshaft
position sensor. I have a pickup coil for it but have
yet to put it on. I really need help with this cause it
is my families only transportation and I havnt been
able to get to work. Any help would be greatly
appreciated thank you so much