Remove the belt, then remove the bolt holding in the idler pulley.
Remove your idler pulley first. it is the pulley right next to the alternator.
3 bolts above your oil filter may have to move belt a
There is a crankshaft pulley, alternator pulley, power steering pump pulley, AC pulley, idler pulley, tensioner pulley, etc.
when looking at the front of the engine it is below the altinator slightly to the right
40 lbs-ft (+/- 5 lbs-ft)
The A/C belt uses an idler pulley accessed from under the car. That lock nut is in the center of the pulley, and the ajustment bolt is located on the side of the pulley.
A serpentine belt has an idler pulley on is to keep it tight at all times. If your serpentine belt is loose, then something is worn out. Its possible the idler pulley is stuck in its bracket so it cannot move or the spring on it is worn out.
Remove belt If you just want to change pulley remove center bolt - it is usually LEFT hand thread If you want to change entire unit remove bolt at spring - usually RIGHT hand thread
Check the condition of the accessory drive serpentine belt, belt idler pulley and belt tensioner pulley bearings.
check to see if the belt is cracked or hard. hard or cracked belts are prone to sqealing. also you can use a stethescope or screwdriver(the cheap way) to listen to the pulley itself. carefull not to get caught in the belt while doing this.
Misaligned or bent pulley. Defective idler pulley. Incorrect belt being installed. The belt must be an exact match, or it will self destruct.