the car is over heating

I am not a mechanic, but I bet it is your headgasket. I had the same problem with my 1998 Deville and it was the headgasket. If you look further down, you will see my post from a couple of months ago (Laoboi). I let my car go back to the dealership because I was not sure if the engine had more damage other than the headgaskets. I have a Nissan Maxima now and I really like it. I did my research and I think I have a good car. The Northstar engine is known for blown headgasket. Go to the Cadillac Forum and read the reviews. Im sure you could have your vehicle fixed..Typical cost is around 2-4 grand.