Well as you are desperate I've given it a go.

Looks to me like there isn't much friction going on, not enough to overcome something in the simulation that keeps it rolling. I guess the answer is either to do something with the forwardFriction of the WheelCollider (but Googling implies that there might be problems here) or to apply some level of braking when there is no throttle.

Here's a stab at that:

function ApplyThrottle(canDrive : boolean, relativeVelocity : Vector3)
{
    if(canDrive)
    {
       var throttleForce : float = 0;
       var brakeForce : float =  0;

       if(rigidbody.velocity.magnitude < 0.01 && throttle == 0) {
         rigidbody.velocity = Vector3.zero;
       } else {

         if(relativeVelocity.z > 0.00001 && throttle == 0)
         {
          brakeForce = -21000 * relativeVelocity.z - 2000;
         }

         if(relativeVelocity.z < 0 && throttle ==0)
         {
          brakeForce = 20000 * relativeVelocity.z;
         }


         if(throttle != 0)
         {
          if (HaveTheSameSign(relativeVelocity.z, throttle))
          {
              if (!handbrake)
                 throttleForce = Mathf.Sign(throttle) * currentEnginePower * rigidbody.mass;
          }
          else
              brakeForce = Mathf.Sign(throttle) * engineForceValues[0] * rigidbody.mass;

         }
         rigidbody.AddForce(transform.forward * Time.deltaTime * (throttleForce + brakeForce));
       }
    }
}

Hey there Mike thanks for the reply :) can you tell me where I drop this into car.js please mate,I have tried different places but keep getting this error ?

Assets/Standard Assets/Scripts/Car.js(595,10): BCE0089: Type 'Car' already has a definition for 'ApplyThrottle(boolean, UnityEngine.Vector3)'.

ps im writing for Android if that makes any difference ?

Im redownloading the untouched car tut and ill get right back to you :) ,fingers crossed :)

silly question im on latest unity 3.5etc would that make any difference ?

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