How to decrease Gfx.WaitForPresent? (2D)

I have an object being instantiated into the scene every two second and noticed that there are huge rendering spikes from Gfx.WaitForPresent. I am wondering if there is a way to decrease this. I tried switching the instantiate from Update() to FixedUpdate() which seemed to get rid of a spike here and there but didn't fix the problem. Any ideas of what is causing this? Here is the profiler:

and the code:

 using UnityEngine;
 using System.Collections;
 
 public class AddMeteors : MonoBehaviour {
     public GameObject MeteorPrefab;
     public float InstantiationTimer = 2f;
     public int MetNum = 0;
     public float speed = 2f;
     public float waittime = 0;
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () 
     {
         Fire ();
     }
     void Fire()
     {
         InstantiationTimer -= Time.deltaTime;
         if (InstantiationTimer <= 0f) 
         {
             transform.position = new Vector3(Random.Range(-6f,6f),transform.position.y,transform.position.z);
             float xdifmin = transform.position.x + 6;
             float xdifmax = 12 - xdifmin;
             float min = (Mathf.Atan2 (transform.position.y, xdifmin))*Mathf.Rad2Deg;
             float max = (Mathf.Atan2 (transform.position.y, xdifmax))*Mathf.Rad2Deg;
             transform.eulerAngles = new Vector3(transform.eulerAngles.x, transform.eulerAngles.y, Random.Range ((-180 + min),-max));
             MetNum += 1;
             var Meteor = (GameObject)Instantiate (
                                 MeteorPrefab,
                                 transform.position,
                                 transform.rotation);
 
             Meteor.name = "Meteor"+MetNum;
 
             // Add velocity to the bullet
             Meteor.GetComponent<Rigidbody2D> ().velocity = Meteor.transform.right * speed;
             InstantiationTimer = waittime;
         }
     }
 }