BT audio standard is older than your car, and the Pixel is nothing new in that regard. Should work unless one of your components, car or Pixel, is defective.
I'll assume you were fully functional with your previous smart phone on BT.
Android phones with Google's flavor of the OS seem to have BT issues for some folks. I've never had them on any of my Nexus phones, but the forums are usually full of complaints from those with issues and their Google Nexus phones re: BT, especially with cars. They seem to get resolved with a software update, or at least people stop complaining.
FWIW, my Pixel XL works flawlessly with my 17 Volt Premiere.
Easy thing for you to check is to go into BT settings on the Pixel, find the connection to your car, select the little gear to the right and make sure all three BT profiles are checked/enabled.
Sent from my Pixel XL using Tapatalk