ve pump question
 

My truck is running rough the problem comes and goes sometimes when ya put it in gear {automatic} it runs rough replaced injecetors added a fuel pin {thought I had a stuck or a bad one }when it runs rough it seems like it loads up when ya step on the go pedal it smokes black real bad egts go higher than normal ??? then all the sudden it'll clear up and run fine the truck doesent get run alot I use biobore ta kill alge the truck is used to trailer cars into my auto repair bus. and that is about it thanks for any help fellas