Motor Trend in describing 13 Cool Facts About the 2017 Porsche 911 writes:
"So much for 'Do No Evil.' There's no technological reason the 991/2 doesn't have Android Auto playing through its massively upgraded PCM system. But there is an ethical one. As part of the agreement an automaker would have to enter with Google, certain pieces of data must be collected and mailed back to Mountain View, California. Stuff like vehicle speed, throttle position, coolant and oil temp, engine revs—basically Google wants a complete OBD2 dump whenever someone activates Android Auto. Not kosher, says Porsche. Obviously, this is 'off the record,' but Porsche feels info like that is the secret sauce that makes its cars special. Moreover, giving such data to a multi-billion dollar corporation that's actively building a car, well, that ain't good, either. Apple, by way of stark contrast, only wants to know if the car is moving while Apple Play is in use. Makes you wonder about all the other OEMs who have agreed to Google's requests/demands, no?"
Update: TechCrunch wrote Google Denies Motor Trend’s Claim That Android Auto Collects Key Automotive Data
TechCrunch learned that when Google initially approached automakers concerning Android Auto, it requested a deeper data set than what is currently required. Porsche could have made the decision at that time to stop working with Google and instead focus on CarPlay. It’s unclear when this early conversation happened. Google publicly announced Android Auto at Google I/O in June of 2014.