I have a 407 2.0 petrol auto 06 . When slowing down to a junction or roundabout if the car does not stop completely and you try to pull away the engine does not respond ,sometimes nearly stalling then suddenly it kicks in and you can carry on . This is very dangerous at roundabouts if trying to pull out in traffic. As there is no workshop manual available for this car which is PETROL I am at a loss as to what to check . Can anyone help please. ???