Can anyone offer any help regarding a rough idle on my 1989 730i. It idles roughly when cold and warm. I suppose it is more of a missfire than just a rough idle. Once you set off it is hardly noticable. I have had the valve clearences checked,changed the plugs(Bosh)leads,distributer,rotor arm,air filter ,checked all manifolds,checked vacum pipes,tried fuel additives but still no cure.Any advice would be most welcome.