Starts and idles alright, but when I try to give any gas, or drive it, it spudders.

As described above, its starts just fine, and idles alright. But when I try to rev it a little, or drive at all, it starts to sputter, and can hardly get RPM's up. It came with a part in a box that was un-labeled, but I believe its a fuel filter. It looks like a small cylinder with a flat, triangle plate on the bottom with 3 screw holes and a little stem coming out of the cylinder. Would replacing this, and having the normal tune-up (plugs, oil, other liquids, fuses etc.) Fix the problem? (The car in the picture isn't mine, thats exactly how mine looks though, just less clean.)