There was no point in beating around the bush. Nathan could only cover for him so far, even Gold agreed with him on that. He could erase evidence of the car's theft so that no one could prove Neal had taken it. But in a small town, with a unique car like that, and a reckless teenager driving it around and drawing attention - he had to do something about it. He could prevent the kid from getting punished for it, but he couldn't let the car remain in his hands.
"It'll be found abandoned on the side of the road near the edge of town. No one will know you took it. But you won't be able to use it again."