Android Auto takover

Not sure if this is a N7 thing or a nougat thing or an android auto thing. Long story short, I mistakenly made android auto my default car mode application. Funny thing is, it was already uninstalled at the time. Now it pops up everytime I put the phone into car mode, but it only flashes the main screen then goes away. I've tried to install it again and disable it, but there are no options in the app manager for removing car mode (reset defaults is grayed out). And even if I uninstall it, it keeps flashing up when I go to car mode (or hit the home button in car mode).

Anyone see this before?
Is there any way to set the default app in car mode so I can force it to something else? Or am I stuck and have to do a factory reset?