Hi scotty. My 04 grand prix is acting up and i hope that i explain it so that u know what im talking about. It happens very random but. At least once every 25 miles or so always when im doing good 45mph or more. Its most common when im getting onto the freeway and accelerating to get speet up to flow of traffic my engine will like almost act as if im about to run out of gas. It like suddenly hesitates then it picks bk up then hesitates then picks back up and it will sputter then accel, sputter then accel like this for maybe half a block and then suddenly kick in and rpms will go up and car will take off as if i have floored it as if its trying to catch up to where it shud have been if not for the hesitation that just occured. It never does it at original take off only when ive already been driving for awhile and only from mid range speed and never more than once every 25 miles or so.