Where is the Idler Pulley Located?

Q: Where is the Idler Pulley Typically Located?

A: The idler pulley is one of the pulleys around which the accessory drive belt is routed. You can take a good look at the pulleys to find the idler pulley. It’s the one that isn’t used to adjust the belt, and it’s ordinarily smooth so that the back of the belt passes over it.

The best way to determine the exact location of your idler pulley is to check your vehicle owner’s manual because its location varies from model to model.

When the engine runs, the idler pulley is responsible for tensioning the drive belts, providing power to crucial components throughout the engine.

Tips on How to Access the Idler Pulley

Accessing the idler pulley can be deceptively tricky and you’ll need tools like a socket set and a torque wrench. It varies though, and on some engines it’s very easy but the belt needs to be removed first.

You may need to deactivate and disconnect the battery to avoid issues while tinkering with your ride. Usually you won’t need to do this though, unless you’re removing the alternator.

Once the battery is disconnected, you can open the hood of your vehicle and remove the drive belt. Before removing the drive belt, make sure to remove the bolt attaching the belt to the alternator. Relieve any tension to make the belt easier to remove.

After the drive belt has been removed, you can freely access the idler pulley for inspection, repairs, or replacement.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: Spin the idler pulley by hand to listen for a bad bearing and feel to see if it is loose laterally.