Chassis, Thank you for your very detailed summary. I sincerely appreciate the time you spend on this. im looking at all the things you mentioned with the dealer, will update you soon!

 

Rough idle is typically one of three problems- fuel, spark, or air mixture. As was already mentioned, fuel pump or injectors don't malfunction too terribly often and when fuel pumps go bad they usually just quit altogether. My first thought is bad spark plug or coil pack. Coil packs are notorious for failing and can cause all sorts of electrical gremlins. In the grand scheme of things, it is a relatively inexpensive fix. You typically see any number of coil related codes thrown though. Just my thoughts. Hope you get it figured out without dropping too much $$.

 

I was experiencing rough idle at cold start and slightly "surging" throttle response past initial tip-in on my '20 Panamera 4S. Eventually, I started getting check engine lights and shortly after the car would go into limp mode. Shut-off and restart would fix it temporarily, but the restart always came after a very long time cranking.

Dealer tried a few minor things, including tightening ground on fuel pump, with no success. Finally, they replaced the fuel pump under CPO a few days ago. Problem seems to be fixed, cold start idle is a bit smoother, throttle response is back to normal, and the power delivery generally feels more linear.