duncanpearce21

Hi to all,
I am new to the MB Forum so please forgive any format mistakes.
I have a 2004 CL500 that has a slight, but irritating tappet noise that can be heard when accelerating away from rest.
It makes no difference whether the engine is hot or cold and cannot be heard at idle, only under load up to about 3000 rpm.
My own guess is a faulty hydraulic tappet (lifter) or maybe more than one?
Is this likely and is there anyway I can do any checks myself before taking it to the Mercedes mechanic?
Also, I have read elsewhere it could be the ABC pump... that does have mild, but regular knocking noise at idle, but I was told this is normal and the suspension raise/lower functions correctly too.
The car has only covered 65,000 miles.
Any suggestions would be great.
Many thanks to all.