While driving on the freeway over the weekend my temp gauge would periodically jump up to high and the check gauge light would come on for about 3-4 seconds and then return to normal for about 5 minutes. Other than the gauge moving, the truck seem to run the same and there was no noticeable noises. No leaks noted when i got home, but there was a hint of antifreeze scent in the air. Any thoughts on whats going on?