for a little while now i have noticed a slight rattle when pulling off, once moving it goes, i thought it was a heat shield some where but looking today its coming from the front of the engine around the top end, it only does it under the initial load of accelerating, any ideas what it could be, my first thought was valve clearance, its a 1.25 zetek with 84k on it, apart from oil changes it has never had any work done to it.