Flipping an upside down car

I just started learning and developing game development using C# in Unity. My first project is creating an object car and making it move.

A problem I have is that when the car hits an obstacle sometimes it flips and can't turn upright again. I want it to be able to turn to its original rotation after some time lying down flipped so the user can continue to drive the car.

I tried this but did not work:

 public Quaternion og_rotation;

 // Start is called before the first frame update
 void Start()
 {
     og_rotation = transform.rotation;
 }

void Update(){ if (transform.rotation.z > 100) { transform.rotation = og_rotation; }

}