Same issue with mine last couple of weeks. turned out to be the TPS (Throttle Position Sensor) I guess it is a common problem. I changed it out twice with a cheapo from an aftermarket parts place only to have the problem come back only worse a week later. I would highly suggest that you get one from the dealer, I tried to save a few bucks and got burned in the end.
2006 SE 6 Speed, Solar Yellow. Zone 2" Hydro BB, Sway Links, and Steering Stabilizer. 31x10.5-15 Bridgestone Dueler AT Revo. Alpine CDA9813, Polk MM6, Polk C400.4