Here’s a company who will help you reduce the amount of data your car collects and stores, especially before you sell it: 

https://privacy4cars.com

This pod is worth the listen too:

https://fountain.fm/episode/xqnGIyMzKRU8SJCLnYNV nostr:note1j3n5evp2ezra2p23kl0dc0h8ucjd72n9mjfnf5xef5sse3e5vv8qyapma3