Since yesterday our car (A4 Avant 96 P reg Automatic coz of wifey) started to have the following problem: From standstill in trafffic/on traffic lights or pulling out of junctions/roundabouts with the foot lightly/heavily on the gas pedal the car moves slowly then revs and jerkes forwards, after that it then drives smoothly with no jerks up to NSL speeds with the usual power. Usually when I'm driving it I just put the foot down at it lifts off pretty well but since this problem started I have to take off like a learner driver and its a bit dangerous at roundabouts and pulling out of junctions. So what could be the cause for this problem. Thanks in advance.