Hi, hopefully someone can help me, my 3.0 multijet is doing strange things, sometimes or nearly always now, when I go to start it, it starts runs rough and will not respond to any thottle, turn it off and restart and its fine ?!? , then when warm if you try to hold say 1700 rpm it revs up and down all over and also if you are on the road with little load at the same revs it feels really jerky as if it is surging up and down, everything else seems fine, plenty of power etc and no warning lights, does anyone know what may be happening or have any advice on what to try to solve it please.....