I went for a run in it today. I was a little wrong with the description, there is no tappet sound as the engine idles on start up, in fact it is as smooth as they come. The noise seems to happen as you are driving, as I mentioned before, it is not a big noise and only sounds like a slight tappet sound. Once the temp gauge reaches operating temp it is gone. The car has been well serviced and is in Mickey Mouse condition throughout, with160,000km on the clock. So I'm not sure it's wear and maybe it's just the sound this engine makes till it warms up? Maybe I'm just being anal, I am use to driving a 5 series BMW and they drive very quietly, who knows, guess I just want to make sure all is well. Thanks fellas for the help on this.