Car Audio Pitch

Hi there, I am struggling with my vehicle’s audio and I don’t know how to fix it? The audio pitch plays on 1 for a second then on 2 the next second going higher and higher. I want it to go smoothly up in the pitch. Any advice I will appreciate.

Here is my car controller script:

function Start () {
	rigidbody.centerOfMass = Vector3(0, -0.05, 0);
	
	mainCamera.camera.enabled = true;
	topCamera.camera.enabled = false;
	driverCamera.camera.enabled = false;
	reverseCamera.camera.enabled = false;
        }
	
function Update () {

	speed = rigidbody.velocity.sqrMagnitude;
	steer = -1 * Input.GetAxis("Rotate Player");
	forward = Mathf.Clamp(Input.GetAxis("Move Forward"), 0, 1);
	back = -1 * Mathf.Clamp(Input.GetAxis("Move Forward"), -1, 0);
	
	
	if(speed == 0 && forward == 0 && back == 0) {
	brakeRelease = true;
	
	}
	
	if(speed == 0 && brakeRelease)  {
	if(back > 0) { reverse = true; }
	if(forward > 0) { reverse = false; }
}
//For Reversing
  
	if(reverse) {
	motor = 2 * back;
	brake = forward;
	ReverseLightObject.light.intensity = 0.0; 
	ReverseLightObject1.light.intensity = 0.0; 
	
	} else {
	motor = forward * -2;
	brake = back;
	ReverseLightObject.light.intensity = 1.0; 
	ReverseLightObject1.light.intensity = 1.0;
}

	if (brake > 0) { 
//Brake lights
	BackLightObject.light.intensity = 1.0; 
	BackLightObject1.light.intensity = 1.0; 
	brakeRelease = false; } 
//Brake lights
	else {
	BackLightObject.light.intensity = 0.5; 
	BackLightObject1.light.intensity = 0.5;
	}
	
	
	frontWheel1.motorTorque = motor_max * motor;
	frontWheel2.motorTorque = motor_max * motor;
	rearWheel1.brakeTorque = brake_max * brake;
	rearWheel2.brakeTorque = brake_max * brake;
 
 	FrontLeftWheel.steerAngle = Input.GetAxis("Rotate Player");
 	FrontRightWheel.steerAngle = Input.GetAxis("Rotate Player");
 
 	FrontSteer.steerAngle = 30 * Input.GetAxis("Rotate Player");
 	
 	if(Input.GetButtonDown("Camera")) {
 		
 		whichCamera ++;
 		changeView();
 	}
 
 	EngineSound();}

and the audio function:

function EngineSound() {

	audio.pitch = speed/10+1;

}

I Hope i Got your problem…U don’t have any gear function…if u had a gear function u can solve that using this Code:
audio.pitch=((Speed - gearMinValue)/ (gearMaxValue - gearMinValue)) + 1;

Like For Gear 1 limit speed: 0-30,then for 2nd one 30-60…just like that…