I seem to have a problem with my Sport mode on my 05 . I was on the highway and got a challenge from a 5 series BMW . I accepted the challange, I pressed the sport mode button and nailed the gas . The car's rpm gauge went to 5000 rpm and never shifted out so I let off the gas and the tac gauge stayed at 5000 rpm along with the engine , the only way I could get it to release was to shut the Sport mode off. Has anyone encountered this problem before ?