How to Replace the Idler Pulley on a 1999 Pontiac Sunbird

The idler pulley on the 1999 Pontiac Sunbird pushes against the serpentine belt and maintains tension to prevent the belt from slipping on the accessory pulleys mounted to the engine. Because the idler pulley is rarely worked on during the car's regular maintenance checkups, the bearing inside the pulley can break down and the pulley can freeze up. This causes the belt to slip on the tensioner pulley. Excessive heat builds up in the belt. You hear squealing and then eventually, the belt breaks. Experienced home mechanics can replace the pulley in a few steps.

• 1

  Locate the idler pulley located at the bottom of the pulley system. The idler pulley attaches to a metal plate with a spring mechanism attached to it. The pulley has a square hole in the middle.

• 2

  Place the 3/8-inch ratchet driver into the square hole on the pulley. Lift up on the ratchet handle and pull the serpentine belt off the pulley. Do not remove the belt from any other pulleys on the Sunbird.

• 3

  Remove the two bolts that secure the pulley to the engine block, then discard the pulley.

• 4

  Secure the new pulley to the engine block using the socket and ratchet.

• 5

  Place the 3/8-inch ratchet driver into the new pulley and lift up on the handle. Slide the Sunbird's serpentine belt over the idler pulley. Remove the ratchet from the pulley.