Hey y’all, I’ve been having it out with this truck for about 9 months… 1999 4.0 ohv 5 speed 2wd.

It had been neglected sitting in someone’s yard for a while when I bought it and brought it back to life but having a persistent problem:

It cranks right up, idles great, drives fine for a couple miles in the morning and then (especially the highway) it will misfire pretty bad ONLY when I accelerate and only for about 5 minutes. It doesn’t always do it, but 9 out of 10 mornings it does. Also occasionally it will do the same thing at random times throughout the day, or especially on my way home from work if it’s been parked for hours, but more often than not if it’s warmed up it runs great, but the problem is getting worse.

I have replaced:
plugs
wires
injectors
upper intake gaskets
pcv
idle air control valve
engine coolant temp sensor
all 3 o2 sensors
cam position sensor
fuel filter
fuel pump assembly
any questionable vacuum lines that I found

Any ideas??