Every now and then on braking the car stops but the engine is racing.I have to keep my foot really pressed not to allow it to move.The panel shows that gear has not shifted down to 1.The techs can not duplicate the problems so they can not do any thing.Any help

 

Check your throttle body, clean it.
Had the engine scanned for codes-what did you find?

The pressure from the engine racing could be preventing your transmission from down shifting correctly or the number is displaying wrong. I would go after the racing engine problem first and see if that solves your transmission shifting problem.