I have a 2008 Prius and have these issues. Engine ICE runs high rpm From cold start thru warm up cycle engine rpm runs high and ICE temps goes to 190 fwt on SG2
Are there any warning lights? You can try cleaning the throttle body and maf sensor. That might help your problem.
Agree, it's probably a gummed up, sticky throttle plate. Can't say I've ever had this problem myself. Unknown if that coolant temperature rise rate and value are significant in this problem. What is "fwt" ? Some other things to check, integrity of O-ring seal on MAF sensor (can be checked when removed for cleaning with MAF cleaner), throttle body to air cleaner junction clamp, binding in the throttle plate shaft to throttle position sensor (from ingress of dissolved solids). From your post, it sounds like this happens all the time. I have noticed a short period of higher RPM in my car when made ready just after refueling. Higher RPM and extended ICE runtime might also be a symptom of a weak 12V auxiliary battery.
I think fwt is what Scangauge 2 shows when engine temperature is showed in degrees of Fahrenheit. 190F is 88c which is normal temperature for engine.
