Yield WaitForSeconds Not Working. Coroutine.

Hey guys. I'm currently developing a First Person Shooter and I've made this code for a rapid-fire Uzi. However, when I tried to slow down the rate of fire using the WaitForSeconds command, nothing happened. Please help!

I've made two different scripts one for shooting and one for sound. Here's the firing script.

 #pragma strict
 
 var Effect : Transform;
 var TheDammage = 100;
 
 function Update(){
 
 if (Input.GetMouseButton(0)) {StartCoroutine(Fire());}
     
 }
 function Fire () {
     
     var hit : RaycastHit;
     var ray : Ray = Camera.main.ScreenPointToRay(Vector3(Screen.width*0.5, Screen.height*0.5, 0));
     
 
     
         if (Physics.Raycast (ray, hit, 100))
         {
             var particleClone = Instantiate(Effect, hit.point, Quaternion.LookRotation(hit.normal));
             Destroy(particleClone.gameObject, 2);
             hit.transform.SendMessage("ApplyDammage", TheDammage, SendMessageOptions.DontRequireReceiver);
         }
         
 
 yield WaitForSeconds(0.1);
 
 Update();
 }

And the sound script.

 @script RequireComponent(AudioSource)
  
 var front : AudioClip;
 
 var back: AudioClip;
 
 function Update(){ 
 if (Input.GetMouseButton(0)) {StartCoroutine(Fire());}
     
 }
 
 function Fire(){
 
 audio.PlayOneShot(front, 1.0);
 
 yield WaitForSeconds(0.1);
 
 Update();
 
 }