Can the car drive evenly on a horizontal highway with the engine turned off?

Since the car is traveling on a horizontal highway, gravity is directed normal to its speed vector and cannot affect it. It would seem that a car with the engine off can move evenly. However, the car is affected by frictional forces from the side of the incoming air, losses on internal friction in mechanisms and rolling resistance associated with deformation of tires in contact with the road surface. All of these factors work to decelerate the car, thus, negative acceleration appears and the car with the engine off does not move evenly, but decelerates.