I have had problems this past winter (and suspect I will see it this winter) with my 2004 Fx4. During cold days (<40degF), while driving down the road after 20-30 minutes, the temperature gauge will go hardover for a period of time and then go back to "normal". Some days it will do it multiple times, other times it won't do it, but I can see the temperature doing some fluxuating before it settles back. This does not happen during the summer time, so I'm confused/concerned why it would only do it on cold days. Thoughts/suggestions? Thanks!