I have read so much on this issue cant place the problem changed tps, fuel filter, iacv, swapped relay positions no change. the truck93 4.0 auto will run great in the mornings and most days when its below 70 degrees outside but on a warm day this problem persists it will start just fine a run great till it warms up then start boggin at red lights and when it starts if i try to rev it up it will backfire through the intakebox aand stall out eventually after runnin horible for a few secs and the oil pressure guage goes crazy then i have to turn the key back and prime the pump to get it to craqnk again but will not stay running untill it sits for about an hour or two ?

 

I just had that same issue over the summer and I replaced all the seals on the intake (upper and lower) and that did the trick. I have a 99 4.0 and it was throwing codes p0141 and p0147 ( if I remember right) witch means it was running lean and was causing it to almost die after sitting at a light. I'm not sure how different your 4.0 is from the one in my truck but I would bet thats the problem.