I assume thats your 94-97 teg in your sig?? it is apparently very common for those years of tegs radiators to crack at the top, it usually happens somewhere betweent 75K and 100K. the top part of the radiator is plastic and the bottom is metal, so they dont get along to well and tend to crack around that time. the only real fix is a new radiator, get a new one from radiator barn for about 100 bucks. this happend to me about 4K ago at 83K miles.