my idler pulley is making a clicking noise, not really all the loud, but loud even you can hear it in the car. first of all is this a problem that will hurt my engine? could i take some WD-40 and spray on it, or would i be better off buying a new one?

 

just buy another one, the bearing is prolly worn out, there like 12$

 

+1 on buying a new one.. if you dont it will completely break on the road and you'll be stuck!! trusy me it happened to me