I have a problem, every time it gets down to about -10F or colder my rabbit gets hotter than in the summer. When I start the car the temp needle slowly goes up untill it's about two notches from redline and then it goes back down to normal and stays there. I have a stock gauge so there's no numbers on it. If it's colder out it takes longer to cool back down and if it's much warmer it doesn't overheat at all. I put cardboard in front of the radiator and it only gets to hot if I work it hard, like uphill or drive in a few inches of snow. I think I have a 185F t-stat. When I got the car there wasn't a t-stat in it, I don't remember if I ran it or not. Does the t-stat think it's too cold to open?