96 4.9 dual tank. Truck runs good, but when maintaining a speed it will bump bump every now and then. No engine codes. don't know if it is fuel, (just put in a new pump) or spark,(just put in new distributor)

Truck did it before these two installs. I thought it might have been bad gas. I just bought the truck, and don't know how long it had been sitting. The parts were not to fix this, but thought it would be good info.

 

Could be moisture. A few ounces of methyl hydrate (in the paint section) will help absorb that and burn it off. Then some injector cleaner in the next tankful (and a new fuel filter) .