New playlist on iPhone 5 not showing up correctly on iPod menu in new car

I created a new playlist via my iPhone 5 on Friday night. When I picked up my new car last night (2013 Nissan Altima) and the salesman was showing me how to use the iPod menu, I went to my "new car" playlist in the menu via the stereo system, however, there are only 5 songs showing in the playlist, none of which are songs that should be on this particular playlist at all. We were stumped because the playlist is in my iPhone as it should be (the playlist does play through the stereo as it should when I select it through my iPhone before connecting it to the car). I thought I synced my phone to my computer yesterday morning, but I wasn't 100% sure so we thought that maybe I just needed to sync my phone. I did that twice since. The playlist is still not coming up correctly on my stereo when I go to play it. All of my other playlists are displaying correctly, it is just this new one that I am having an issue with. I am stumped. Any ideas?

Also...I am using a USB connector, I am not sure if that makes a difference.