Alrighty, it is a manual transmission.
It does this in and out of gear.
When the vehicle is in gear, it will get to the speed alotted for the rpms (say 40 mph for 2100 rpms in 5th gear). It then sounds like the engine is choking, and the vehicle jerks if I try to go over that speed, however if I stay at that speed, it works fine.
Also, when I down shift, this "barrier" goes away, until I push the gas pedal.
when sitting still, it sounds like the engine is choking or trying to backfire but it doesn't quite get there. If you've ever played a video game and just pushed the gas pedal all the way down and listened to the game's interpetation of what would happen without the engine blowing up, my car sounds like that.
Like its trying to go past a point, but it chokes or backfires or runs into a wall.
The vehicle is not actually backfiring as in shooting flames and nothings gettin hotter than usual.