Hmmm.. I think that 90*C is acceptable from what I have heard, but I do not like to see my temperature above 80*C, which it does occasionally do when it is above 60*F outside and I am in stop-go traffic, then it goes to about 85*-90*C. I have not owned the car that long, (about a month) and it has only been in the 40s-60s, so I am hoping that when the temperatures soar into the upper 80s and mid 90s this summer that it will not be anymore of a concern for my car. Meaning, I hope that 85*C is the highest it will go. When I am on the highway/freeway, it will drop below 80*C.

I am soon placing MB/Zerex coolant in place of the green coolant, so hopefully that will help as well.

I understand what you are saying however- you are wondering why it is reading higher now that before. I wish I knew. I am sure someone here will have more info regarding this.

Good luck.