3406b missing allen screws from pump??

Let us know. Hope this does the trick.

 

You been running it all week and still off and on?

 

Alright man, time to get serious I think. We've gone through the obvious issues. Problem is either in the fuel pump or an injector problem. My money is on the pump b/c when you bought the truck and removed the cover those screws have been tinkered with. Somebody played around in there and over adjusted something. Did the truck always do this since you purchased it?

 

check the timing advance on the older style units when they get really worn ( high mileage ) it will start to float and timing becomes random runs like a V12 sometimes then runs like a 8V71 next then won't hardly run at all kinda rare but it happened to me good luck

 

The advance slipping is a possibility, getting fuel and it running right could be a coincidence. Usually if advance is slipping it will have a bad timing rattle sometimes other times it won' t. You can tack weld it if that's the problem

 

The timing advance being worn is an odd problem. However, the issue you have is sporadic. Something is def. played out. I agree timing could be it. Going back to the fuel adjustments if someone over adjusted or simply just had too much fuel flowing through there, sometimes once you turn them way up they have trouble being turned back down. The springs and plungers get stretched and worn. I only bring this up because when you started this thread you had pics of the fuel adjustments and somebody was def trying to get max fuel flow through that pump. Always hard to find a problem when your digging through somebody else's wrench turning.