2012 Jaguar Xj

The engine has issues where there is a jerk while accelerating at times. I was told of a misfire issue that Jaguars have and have not been corrected. I was driving my 2012 Jaguar XJ on the interstate when it started slowing down. The engine light than appears on the dash and it starts to jerk as I try to speed up to get off the highway it goes from 60mph to 45mph. I take my foot off the gas and press the gas again for the car to jerk and accelerate slowly back up to 60mph. Not only was I almost hit from behind but almost crashed trying to get over and off the road for my safety and others. I was told by a mechanic the car needed a new gas treatment, fuel cap, and tune up all this money paid and no results. The 2012 Jaguar xj still stalls when accelerating. The buttons are melted into a gummy substance and a barely used sunroof wont close has a loud noise when button is touched to try and close it. Worse experience ever with my 1st and last 2012 Jaguar XJ.