Quote Originally Posted by kybarry View Post
I'm not sure what case it is, but this is an exception with verbs of motion going home, specifically. You only use this when you are going домой, at least I can't think of another one like it.
I think the exception you speak about is word "домой" but Pippynip asked about translating "by car" as far as I understand.

"домой" is an adverb and can not take any case.