Last week the NHTSA issued a recall for 17,986 Panameras and Cayennes built between 2010 and 2012. The affected vehicles are Panamera S, 4S and Turbos built between 2010 and 2012, and Cayenne S and Turbo models built in 2011.
The issue relates to the camshaft controllers in the Porsche V8, which may come loose and fail. Per the NHTSA this condition can cause the engine to stall, though the sources do not indicate engine failure caused by this issue.
What to do if you think you own an affected Porsche
At this time Porsche has not released a repair or owner notification schedule. If you own one of the potentially affected vehicles, you may Porsche customer service at 1-800-767-7243. Porsche's recall number for this issue is AH08.
Porsche will notify owners, and the camshaft adjuster fastening screws will be replaced by the dealers free of charge.