How do you change a idler pulley on a Chevy Colorado?

To change the idler pulley on a Chevy Colorado, first, disconnect the negative battery terminal and relieve any tension on the serpentine belt using a wrench on the tensioner pulley. Remove the belt from the idler pulley, then unbolt the idler pulley from its mounting bracket using the appropriate socket size. Replace it with the new pulley, reattach the belt, and finally reconnect the battery terminal. Make sure everything is secure and test the installation by starting the engine to ensure the pulley operates smoothly.