Now that you're really, let's turn to your car. It's a wealth of information about you and yours, luckily a lot easier to manage than the social network. Here are some tips that will work in almost every late model car.
Paired phones: These are easy to delete when you sell, loan or service your car. Pairings don't do much without the phone nearby, but we're being paranoid here in the first place.
Phone contacts: Do you really want to sync those when you pair your phone? Just say no when prompted, but be ready for some messaging inconvenience on the road.
Destination history: Your car's nav system has a nice record of everywhere you've charted with it, without so much as a password on it. There may be a menu to erase those wanderings in your navigation settings.
Just wipe it all: More and more cars have a single menu command that will take care of all the above, as well as blowing out your personal settings, from radio stations to seat adjustments. All that's left will be fingerprints and your name on the title.
Black boxes: Properly called Know if your state has rules about who can get the data. And since 2006, new cars have had to come with a notice telling you they have a black box., these have been common since the late 90s and record a rolling snapshot of your car's controls and how you were using them. They are not meant to be fiddled with, but an accident forensics company can probably do so for a price. I don't advocate evidence tampering.
Hidden GPS trackers: If you have good reason to fear someone has installed one of these on your car, you either need a good divorce lawyer or a sympathetic contact inside the NSA, not a Roadshow article.