OK, the beast has been backfiring, bogging down in the cold and popping and pinging when I blip the throttle when it is warm. On freeway onramps (especially those hard right ones) the car literally stumbles and two times has gone into limp home mode. The MAFs were replaced as that was the code at the dealership that stated a probem. Car runs better, but still stumbles and just again today went into limp home mode on the same onramp. So...fuel filter, pressure regulator, coils? Has anyone else had this issue under cornering and acceleration?