I have a 05' x5 4.4i. I was driving at slow speeds (below 5mph) when I tried to accelerate. The engine speed went up then suddenly the car (SAV?) lurched forward as though I had been hit from the rear. I took my foot off the gas and tried again. Same thing happened. Then a warning message came up on the dash. It read " trans failsafe mode". I parked, restarted the car and the message was gone. I have had no problems since (2 days). The dealer wants the car overnight to check it out - says its a programming problem. Whats the deal?