So the other day i was driving my car, the battery died that day, (has a small drain) anyway i jumped it, and all was well. then i started driving on the highway. and the car would literally feel like it was getting a fuel shortage (felt like missing almost) around 2600-3200 rpms, that whole range. so i get to work and decide that to be safe i would disconnect the neg battery cable so i dont get stranded. then on the way home it ran like a champ. But yesterday i decided to take out the stereo so i disconnected the Neg battery cable and then drove to work today and it sputtered again. so i did what fixed it last time and disconnected it. and it worked.

What do you think may be causing this???