If you're looking for privacy you might as well buy an older model and put in a Bluetooth stereo replacement in it.
You're not going to find a modern car that isn't spying on you.
outside of sandboxing/limiting android auto via grapheneos good luck.
if you just want audio & your car doesnt support Bluetooth you could use an adapter to take it from Bluetooth to 3.5 aux. if your car is so fancy it doesn't have aux input you can get a Bluetooth to FM radio adapter that will take over one the channels in your car as well.
Connect it for what purpose? Audio only? I've bought a Bluetooth to Aux-In adapter, it's a tiny USB dongle that pairs with your phone, and sends audio to the line-in port of the car radio (if you have one).
Something like this: https://www.amazon.com/UGREEN-Bluetooth-Receiver-Audio-Cable/dp/B081GGB53R/
Edit: My car doesn't support Bluetooth out of the box, hence this workaround.
Hi! One thing you could consider is using GrapheneOS which supports Android Auto without special priviliges!
I actually don't know if newer cars can just use Bluetooth without an app. I've been thinking of replacing my car with something more practical which is why I posted this. I don't know how much privacy newer cars have left.
Unless it's changed in newer car models, Android auto only connects when you physically plug it into one of the provided USB ports in the center console/glove compartment. The BT connection only allows media and phone usage (audio and SMS). You won't get maps or other apps to appear on the in vehicle display, though.
Some car infotainment systems have settings where you can set them to only connect to your phone via bluetooth and not apple carplay/android auto