Every motorcycle sold in the U.S. for about the last 40 years has an engine kill switch located in a standardized location. It would be quite easy to add this feature to cars. Want it off? Hit the kill switch. Want it back on? Turn the kill switch to "run" and hit the starter. Easy day.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.