Hello, i own a 2012 panamera 4s and two weeks ago I was experiencing an issue with my car.
I noticed that everytime my rpm went a little high wether the car was rolling or on park, it would indicate that there a psm failure and start/stop mode was deactivated. After that, while trying to drive along despite these messages, the engine would make a rough noise and the pedal wouldn't take as much gas as before.
After that, i turned the car off and let it rest for about 5 mins then turned it on again, the messages were gone but it gave me a check engine sign.
I called the porsche company and they said that the problem was from the ignition code responsible of activating the spark plug and charged me 350$ for the repairments.
Do you guys think the problem was cause by the ignition or is there something else we're missing?
Thanks and sorry for the long thread

 

I experienced that 1 day right after I got my ptt. Scared me. They replaced a coil pack. Problem hasn't returned.

 

How much did it cost u?

 

Nada certified was under warranty