Yeah, the deal is that it's very problematic.
Just do a search for "car" and "bluetooth" and you'll get an idea what you're up against.
Synopsis: lots of people seem to have similar issues, particularly with contacts not transferring, or with song titles not showing up on the head unit.
Solution: some folks have had luck by getting the latest firmware for their respective automobile. Others have fiddled with the bluetooth configuration of the car (A2DP comes to mind) and gotten it to work. I even saw a post from some guy that got a newer car! But it seems like a lot of people ended up with no solution.
I've got a really old POS Ford Mustang without any of these features so what I'm passing along is just from what I remember reading, and not from actual experience. Good luck.
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