The temperature gauge in my 99 grand prix gt rises at idle, but never past 210 and then goes back down to while driving. I had a leaking radiator ane replaced it as well as both radiator hoses, thermostat, and cooling temperature sensor. After replacing these parts it stays at 210 while driving but goes up just before the red zone. Does anyone have any ideas as to what the problem could be? Please help. Thank you in advance.