We picked up a 2011 Regal for my wife earlier this year, standard 4 cylinder 6 speed transmission. I found a thread in this form were others have had very similar circumstances. 2011 Regal Issues Need Input!
Same problem with hers, cruising speed, slower speed or sometimes during acceleration it donít matter. The car will usually go into a protection mode or safe mode, it will tell you on the display behind the steering wheel that the ďVehicle is in reduced power modeĒ or something similar. Often it will drive like that for a period of time then just kill. I can keep it going if I put the transmission in the manual shift mode; it seems to prolong the problem but doesnít fix it. The Check Engine light and just about every light associated to the braking system will come on. Most of the time it is just the Engine and the Traction control light that will remain on for some time. Like others I can get to the side of the road and restart the engine after about 20 seconds and it will go back to almost normal. It will trip the engine light and it will remain on for a period of time. The car has straight up shut down on several occasions, kind of wicked when your cruising 70 mph. Been in for service 4 times, two times they read a Throttle position sensor code, (I wasnít buying that) they replaced it anyway, didnít do anything. The next time they said there was low voltage to the ECM (wasnít buying that either). The dealer said they put 110 mile on the car and it ran fine, I put 173 mile on it from their parking lot and BAM on an exit ramp it flat out killed, the same warning lights came on but it only took a few seconds and it was dead. I read that the fuse for the ECM could be the culprit, so I called the dealer to located it (#2 top row) I took the fuse out it looked fine so I spread the contacts a little to see if it may help create a better connection, Iíll know soon enough, the car seems to do this at least 2-3 times a week. If this does not fix it itís going back in and they are keeping it until they can figure this out. Has ANYONE found a cure, fix or reason why this happens, please let me know.