when you say sharp turns, do you mean when the wheel is turned all the way to one side? Does it do it when you turn both ways? Does it only do it when the wheel is turned all the way, or just when you turn it at all? If you have these kind of symptoms, it could be your drive axles. Go to the front of the car and take a peak under. Look ot the inside of the wheel and you will see a shaft with a black boot on it. If the boot is torn, you need new axles and that is what has caused your problem. Good luck.
Dan