Surging idle and stalling? About 5 to 8 seconds it starts to cough and sputter?

Truck starts just fine, after about 5 to 8 seconds it starts to cough and sputter then catches itself and revs up to about 2,000+ RPMs then back down and coughs and sputters. Cycles like this for a minute or so until it eventually stalls or evens out and idles. When it idles it's not smooth and won't accelerate? If the accelerator is pressed or it's put in gear it stalls. On occasion it will start and idle, not a good smooth idle but stays running, can rev it and drive it, doesn't run well, but will drive. Once it's turned off and restarted the coughing cycle starts over.
Started one day leaving work ran fine to work but wouldn't run in the afternoon. Towed it home found the fuel pressure a little low 46-47 PSI. Changed fuel pump, no improvement to the coughing. Eventually I found a sizeable vacuum leak in the PCV line. Repair the line no improvement. Vacuum at manifold holds steady at 20in when it stays running. No DTC set no pending DTC. Not sure what else to look for with no DTC. Forgot to mention fuel filter was changed with new pump install.