iv got a s2 rs turbo and its got a realy bad rattle its worse when i first start the car then after 2 or 3 sec's it dies down a bit,but gets louder when i rev the engine.i have replaced the tappets,it sounds like its comeing from the top of the engine at cam belt side.my mate said he had the same prob wiv his and it was the big ends.is there any way of telling which one it is. please help coz its killing me haveing her off the road.