The quickest thing that comes to mine when dealing with my century is the I.A.C. unit or intake air control. if your idleing rpm fluctuates when heated up and eventually just dies till it gets cooled down, its a probable cause. they can be cleaned but your most likely gonna wanna just replace it for 46 bucks in no time by yourself. As long as you don't handle it roughly they callibrate themselves so no worries. worth a shot.