I purchased a 2016 4x4 limited grand cherokee on Sept 9th 2016 from ACADIANA DODGE here in good ole lafayette, la. . Last week sept 30th (which is really the first time I had driven the vehicle for a long period of time, in this case it was running around town all day because my main vehicle was in the repair shop having brakes done. I purchased the vehicle with about 150 miles on it. AS I said I had driven it from the store and back but not for longer than an hour or so. This particular day I was in the vehicle all day. In and out, driving across town. The vehicle at that time had 548 miles on it. After driving all day as I said, I go to get on the interstate (which was the first time all day of getting the vehicle up to high speeds), as soon as I got the vehicle up to about 55MPH for about 5 mins, the engine stabilizer light came on and check engine light come on and immediately the vehicle slowed down to 40 miles an hour. I am in the fast lane at the time passing another vehicle with another vehicle on my tail in close proximity. So as I am trying to accelerate the vehicle refused to get above 40 miles an hour, so the guy behind me had to slam on his brakes due to my sudden deceleration and I can see him cursing and shooting the finger at me. at that point I knew I had to get out of harms way so I pull over to the inside shoulder (not much of a shoulder there) and call road side assistance. It's after 5 so dealership is closed. So knowing I would have no way to get to my other vehicle I limped along on the shoulder until I could get to some back roads to make it home. Vehicle get's towed to dealership. They kept it for 2 days and called me and told it was ready but wasn't sure what the issue was so they said they changed some wiring harnesses and a cam something or nother. So me not feeling confident at my service guys answer to what was the issue, I decided to drive it for the next two days. On the second day (2 days out of the shop) low and behold the EXACT SAME THING HAPPENED. Again almost causing a major accident with the vehicle decelerating rapidly at to 40 mph from 60. Car behind me you can hear him squealing his tires trying not to hit me as I tried to quickly turn off the exit before he slammed in the back of me. I was lucky again. Now the vehicle has 640 miles on it as of today and is back in the shop having it towed again for the same issue which they do not have a clue what it is. I have demanded a new vehicle and contacted a lemon law attorney. I will never buy another JEEP NOR WILL I EVER BUY ONE FROM ACADIANA DODGE in Lafayette, La.