On at least 4 occasions in the last 20,000 miles (now have 65,000 miles on the car), while driving at normal speed, engine starts to "spudder", seeming like it is running on 4 out of 8 cylinders. Engine then cuts completely off and all traction control and engine lights illuminate. This is all precluded by about 1 or two days of engine hesitation and a "whining" mechanical sound around passenger side firewall. Once engine cuts off, it will not restart. After waiting about 15 minutes, computer seems to reset itself, restarts, but engine light remains on. We take it to the dealer and they can never replicate. Waiting for this to happen on the highway and get rear-ended by an 18-wheeeler !!