td4 belt tentioner

Auxiliary belt tentioner PQG100340L , could this be responsible for a annoying rattle at idle , that goes with a slight increase in revs , I have checked all the pulleys for any play , and this was the only one that had movement , although slight but enough to make a plastic to metal sound , any one had this rattle and cured it by replacing the tentioner , any help or advice on this would be most appreciated

No response on this , a bit disappointed , life goes on , problem now sorted , I know there's a few rattles on a freelander , this one has been bugging me for nearly 5 years now , sounding like a plastic resonating timing chain noise , that went when rpm was increased , replaced both belts and noise gone stretched ancillary belt causing said rattle , hope this helps someone in future diagnosis , thanks for all your input NOT ! , MY td4 engine now sounds sweet !