If you have been one of the many that have suffered with the bluetooth bug on the Pixel and Pixel XL it looks like Google may have issued a fix via server side update. An early bug in the Pixel was causing failed bluetooth connectivity in cars. A new issue came up later after the release where bluetooth devices would randomly disconnect. These issues reportedly started after the February security patch.
A Google Team member has reported in the Pixel User Community forum that Google has just put together a fix for the issue. He went on to mention that no downloads or installs will be necessary indicating it was a server side fix. While the issue is claimed to have been fixed some users are still reporting bluetooth problems. The update began rolling out as part of the Google Play Services update March 21. The update may take a few days to hit your device. Has anyone seen a change? Has this issue gone away for you?
via Google