Engine noise

[chriscdm]

Hi I have a 2.2 hdi with 106k miles it seems to have a knocking / tapping nose coming from the engine at idle speed and goes away after around 1200k revs there is no loss of power a friend sugested it is piston slap if so is this a serious issue ? hope someone can help

Thanks

[Peter.N.]

Could be, although its not common nowadays, I would think its more likely a worn or blocked hydraulic tappet.

Peter