ive got a mark 4 vauxhall astra 2005 sport, the car drives perfect in every way apart from after some high spped on a motorway when releasing my foot off the accelorator the car will squeal like mad, as soon as i put my foot back on the accelorator the car will shut up, occassionally at a junction if i have to stop the car will cut out and the brakes will go a bit hard, has anybody else had this problem and what it is, ive recently had a new coil pack, cam belt kit done, tensioner belt and a new water pump