What is the Drive Belt Tensioner all about?

A Drive Belt Tensioner is a pulley mounted to either a spring mechanism or to an adjustable pivot point that is used to keep constant tension on your serpentine belt. That is the big long belt in the front of your engine. The tensioner rides on the outside surface of the belt to put pressure, or tension, on the belt and against the pulleys that drive things like the alternator, power steering, air conditioner, etc.

Keep in mind:

Tensioners usually come with pulleys; they are normally replaced together. Also, when replacing a tensioner, the drive belt usually must be removed. A mechanic may recommend replacing the belt as well.

How it's done:

• Check for any noise in the engine (usually a squeaky or grinding noise).
• Remove the drive belt(s) (in most cases).
• Inspect drive belt pulleys.
• Check the drive belt tensioner.
• Remove and replace the tensioner if faulty.
• Start car to see if noise is gone.