hi can anyone help i have just bought a 2006 seat leon tdi deisel lovely car economical fast . engine has a tapping/light knocking sound around the top end cam cover which only becomes audible above 2000rpm. friend has had a look and thinks it could be a follower and it may be possible to shim it or replace it, i have spent hours on internet trying to find info on noisy bkd engines no luck. anyone any ideas cheers walshy