How do you change the idler pulley on a 1998 delta 88 Oldsmobile?

To change the idler pulley on a 1998 Delta 88 Oldsmobile, first disconnect the negative battery cable and relieve any tension on the serpentine belt using a wrench on the tensioner pulley. Remove the serpentine belt from the idler pulley, then unbolt the idler pulley from its mounting bracket. Install the new idler pulley, ensuring it is securely fastened, and reattach the serpentine belt before reconnecting the battery cable. Finally, start the engine to check for proper operation.