2006 Nissan Sentra serpentine belts

Hello,

If it is a 2.5L engine there is a tensioner assembly and the tension is adjusted automatically. However, there is a possibility that the tensioner is bad. Also, if you are hearing a squealing noise from your belt it is also possible that the tensioner pulley bearings are going bad. One way to find out is to take a can of wd40 or similar and with engine off spray center bolt of tensioner, start vehicle if squealing is gone for short period then replace pulley.

If it is a 1.8L engine it has an Idler pulley and same could be wrong with it as far as the bearings. Do the same test as above to check bearing.

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