There are lots of reasons to want to shut off your car’s data collection. The Mozilla Foundation has called modern cars “surveillance machines on wheels” and ranked them worse than any other product category last year, with all 25 car brands they reviewed failing to offer adequate privacy protections.

With sensors, microphones, and cameras, cars collect way more data than needed to operate the vehicle. They also share and sell that information to third parties, something many Americans don’t realize they’re opting into when they buy these cars. Companies are quick to flaunt their privacy policies, but those amount to pages upon pages of legalese that leave even professionals stumped about what exactly car companies collect and where that information might go.

So what can they collect?

“Pretty much everything,” said Misha Rykov, a research associate at the Mozilla Foundation, who worked on the car-privacy report. “Sex-life data, biometric data, demographic, race, sexual orientation, gender — everything.” . . .