Has anyone experienced with the 2024 Cayenne (brand new, driven 2000 km) suddenly showing a fault message "Engine control unit error, you can continue driving, please proceed to the service center"?

I haven't encountered that. [Grin]

Turn off the car and restart it, and usually the issue goes away. The EA839 isn't that delicate. I've encountered this problem too, and basically, it's just a matter of shutting down and restarting... That's how Porsche is.

I've encountered it before, but didn't bother with it later.

Some people have encountered this issue, it's best to go to the 4S dealership for a check as soon as possible.