Vehicle is a 2006 Buick Lucerne cx with 40,000 miles. About 2 months ago it started to go dead without any warning. The first occurrence was Jan 15, 2014 with my wife driving. The next shutdown on Mar 4, 2014, occurred in rush hour traffic. There was an audible signal accompanied by a "service traction control" warning, followed immediately by a throttle control warning and complete engine shutdown. I was able to coast across 2 traffic lanes into a parking area with great difficulty while steering and braking without power assist. Tried to restart the engine but got "throttle disabled? message. After 2-4 minutes was able to restart with no warning light illuminated. The last shutdown was on March 10, 2014, on the interstate at 70 mph. I had disabled traction control earlier in hopes of avoiding another unexpected shutdown. After coasting off the interstate, I was able to restart normally after a few minutes. No warning lights appeared after the restart. Two GM dealers checked the car on Mar 11, 2014. The first was a Chevrolet dealer, and after some diagnostic work they sent me to a Buick dealer down the street. Both dealers said there were no error messages and they could not repair. They said when it happens again to bring it back in immediately for diagnosis. The 3 shutdowns have been on cold mornings, temps less than 40 degrees. I believe in all three cases the warning ?watch for icy conditions" has appeared prior to failure. This is an extremely dangerous failure mode that leaves no tracks if there is an accident! my wife now refuses to drive the car, and I am very apprehensive about it.

- Cordova, TN, USA