One problem related to wiper has been reported for the 2017 Porsche 911. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2017 Porsche 911 based on all problems reported for the 2017 911.
The rear window seal is severely breaking apart, severely cracked and others are melting. This may affect condensation inside the vehicle and potentially be a safety hazard. Several reports on this problem can be seen at Porsche forums. I believe this is a manufacturing defect and is a potential safety hazard on many Porsche vehicles.