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To your first question, define "all"... to most people the answer will be "yes", the car logs a lot of data; and, specific information is always being sent to Tesla (provided 3G connectivity), to include location, speed, etc. The Model S did not win the prestigious Ashley Madison "Marital Infidelity Car of the Year" award, nor is it the car - despite the sizeable rear hatch and frunk - that you, Tony, and Vinnie should be taking to go do "that thing". I do not know the retention time of said logs, but given some of the successful troubleshooting stories here, I'd assume it is considerably more than the average vehicle.
To your second point, I'm not sure whether there is a process to ask that data be flushed. Your telematics agreement, signed when purchasing the car, includes the provisions of data collection and authorizes it.