Glitchy Turret Script

Hey everybody. I have been working on a turret script, but it does not seem to be working properly. I have set up a series of booleans, I made it so that if the object tagged enemy enters the trigger Look is true and the turret would rotate around and fave the object. Also when the object left the trigger, it would stop looking. Then I tried to make it shoot as seen in the code below. But it will work(as in look and shoot as it is supposed to), or it wouldn't work (randomly stopping and then would stop shooting even when the object was still in the trigger). It really is hard to explain so please try it out in a unity scene. Here is the script(ignore the comments):

 var Look : boolean = false;
 var Target : Transform;
 //var Dead : boolean = false;
 //var Health : int = 10;
 var damp : float;
 var Projectile : Transform;
 var fireRate = 5;
 
 private var nextFire = .5;
 
 function OnTriggerEnter(other : Collider){
  if(other.gameObject.tag == "Enemy"){
  Look = true;
  }
 }
 function OnTriggerExit(){
  Look = false;
 }
 function Update(){
  if(Look){
  
  var rotate = Quaternion.LookRotation(Target.position - transform.position);
  
  transform.rotation = Quaternion.Slerp(transform.rotation, rotate, Time.deltaTime * damp);
  Shoot();
  }
 }
 function Shoot(){
  if(Time.time > nextFire){
  nextFire = Time.time + fireRate;
  
  var projectile = Instantiate(Projectile, transform.Find("Spawn").transform.position, Quaternion.identity);
  
  projectile.rigidbody.AddForce(transform.forward * 1000); 
  }
 }

Any help at all will be appreciated.