A while back I had a no start condition, and found that the crank sensor was out. Soon after the starter drag from time to time with a click ,click. I found a use starter ,replace it my car ,it worked fine for about a week and went out . Got another started ,tested it before putting it in the car seems to be fine , get home put it in and car does the same thing it did when I replaced the other use starter . I am thinking that theres something else wrong with the car , but which way should I go? Crank sensors is only 6 mos old, the starter is used but was working yesterday, and not sure if the key could be the problem. Need help with the checks.