Engine Stalled

Hello, I'm new to this forum because I just bought a Jaguar Last week, XJ8 2000 w/66k miles, and I love it.

Anyway, I had my first problem I made a sharp u-turn last night and the engine stalled on me. This is my first Jaguar, I don’t know what this might be, I called the dealer who sold me the car and they said to drive it for about a week it just might be bad gas or something and if the problem continues bring it in for a check-up, they claim the car was fully serviced and had no problems before it left the lot. Any thoughts on this? I do have a 12 month warrantee.