Hi my name is frank and I just purchased a 1997 Deville base sedan 150k, this is my situation with my car when I'm driving the temp goes to 222 fans turn on and its bumped down to 217-213 then when I start driving or idling in town it starts climbing back to 217, 219,220,222 then back down again. When I get on the freeway entrance and I start to accelerate the temp seems to go up a few degrees(temp starts out at 217 goes up to 222). When I get on the freeway and the engine temp is 222 it doesn't go any further, it starts to drop to about 196 -190 188 in about a minute or two of driving and stays there. On the freeway if I floor the car on the freeway the temp doesn't go up it actually makes the temp go down more. I put a bottle on the overflow hose and theres no water being blown out its dry... I replaced the water pump belt because it looked wet and damaged it was falling apart I didn't notice and leaks around the water pump or anywhere else around the engine. Help.