I REALLY need to get a Faraday bag, now that I have a keyless-starting car..
"Auto technology has evolved and many newer cars use wireless key fobs and push-button starters instead of traditional metal keys. The fob sends a short-range signal, so when the driver approaches the car, it automatically unlocks the door. This saves you the hassle of digging out your keys when you've got your hands full with groceries.
But
that technology also makes things easier for thieves. The wireless fob will continue to emit a signal even if you're not using it. Thieves prowl neighborhoods at night looking for cars parked outside so they can carry out so-called relay attacks. Using portable equipment that can pick up the faint signal from a fob inside the house or parking lot, they relay it back to a transmitter that can clone the signal."
https://www.yahoo.com/tech/one-tech-tip-protecting-car-083947033.html