I had the 308 GTB out for a good run today. One thing that was a concern was the Water Tempature Gauge. Most of the time is was fine. Sat right at 90 degrees or less on the highway. As soon as I got off the highway and had to wind my way through a few towns, it moved up quickly to the 105 range. Never much above this but still a concern. I did check the radiator fans and they are working perfectly. Any suggestions ?