I have an 06 4WD AT. It has been sputtering when at low RPMs. I took it to NAPA where they ran a test with their little computer. The code came up 0301 which means the #1 cylinder is misfiring. I have changed all spark plugs and #1 coil pack. Still not running any better. I am thinking now I need to change the fuel injector on #1. Any thoughts? I have seen others post about the same problem. I have an appointment with the dealership but I'm nervous about the cost. Any help would be appreciated. 
