I don't see the car.
Actually for this one particular sentence a different word order sounds more natural.
As it is it would be insisting on the fact that you can't see the car, like s.o. told you to look at the little green car over there and you said: Sorry I don't see it. He answers back: It's right in front of you... And you say: I really can't see it.
If the situation is that you are just coming back from a walk and say, Where's the car ? I don't see it...
Ich sehe nicht das Auto.