Pulley on side off engine?

  1. #1
    on the 306gti 6 to be percise, what is the pulley next to the alternator pulley called? there is 3 on there 1 crank pulley other alternator pulley.. is it idle tensioner?

    Help please? mine is sqeecking so gunna change it!
  2. #2
    could be power steering or a belt adjuster