7.3 idi cranking but not starting

So I have been driving my 93 f250 lately because a deer totaled my 06 mustang. It wouldn't start when I tried to start it after sitting for 6 months I replaced the batteries and it started for about 20 seconds very roughly and then died and couldn't get it restarted didn't even sound like it wanted to. Before it sat it ran great I had a local shop test the glow plugs and some were weak and some were bad and only one good one so they replaced those and It started up roughly, it ran smooth after that except sometimes when I stop at idle it starts to run rough and sometimes it would start and then cut off but would restart after that, it just did that to me and then it wouldn't restart it just cranks, I thought maybe the solenoid is weak?? But I can hear it clicking and power going to the glow plugs, but that wouldn't explain the rough idling once it was warm, any ideas??