My new (to me) 2004 ST3 runs rough, kind of spitting/stuttering, below 3,000rpm, even when the throttle is closed. Otherwise, it seems to run great. Another thing that may be related is that it idles at 1,500rpm and I wonder if the TPS needs to be reset or the "trim" adjusted. Does anyone have any recommendations on how I can correct this condition? Any suggestions would be appreciated.