Hi I have a 2004 Dodge Ram that when you are in a stop sign or in a light stop the temp gauge goes up more than half . Also this only happens when its over 90 degrees outside meaning where I live always. During morning hours on late night hours it doesnt do this. We already repaired the radiator last week it worked fine for the whole week until now it started doing the same thing again. What do you guys think it might be???