Is tension lost on a broken spring while still car?

Yes, tension is lost on a broken spring while still in the car.

When a spring is broken, it loses its ability to store energy. This means that the spring is no longer able to resist the force that is applied to it. In the case of a car, the force that is applied to the springs is the weight of the car. When a spring is broken, the car will sink down on that side. This is because the spring is no longer able to support the weight of the car.