I have an 04 GC Special Edition and got this code about 2 weeks ago, had it read and reset, then it came back about a week later. From my local autozone, the readout "probable causes" are (1) fuel cap, (2) Evap cannister broke or hose leak, (3) purge solednoid defective, (4) vacuum leak at engine.
I'm approaching this methodically. First I'm going to discount the fuel cap by wrapping saran wrap around the cap before screwing it in to eliminate the cap as a possibility. I'm in the process of checking this now. Next I'll check for leaks, not sure how to easily do this, any suggestions??