Hello,

Only with the air conditioning running and only when I go into reverse, there is a belt squeaking intermittently. Shop looked at belt auto-tensioner but adjustments made no change. Any ideas?

Thank you!

 

No adjustment possible on an auto tensioner.....is the belt cracked or glazed?

 

Martyman is correct, no adjustment on the serpentine belt tensioner. If belt is not cracked or glazed, try this: withe engine OFF, see if you can move the tensioner arm with your hand, if you can, the tensioner is bad and will need to be replaced (common item on our cars).

 

Only with the A/C on makes sense--that's when maximum stress is on the belt. Only in reverse is a little puzzling--that's when the engine shifts position in the cradle. But all the spinning parts are attached to the engine. Sure sounds like a bad tensioner. But, it's easy to diagnose if your mechanic has a set of Chassis Ears.

 

Thank you everyone for the info. I will check tomorrow to see if it is the tensioner arm and let you know.

 

With the squeaking is happening spray a VERY small amount of water on the belt - a tip from my father who used to work for Gates. If the squeak is caused by slippage then the water should stop it temporarily. If the belt is in good condition suspect the tensioner. As well as trying to move it by hand use a wrench to release the tension. The spring can loose its springiness with time and fail to reapply tension properly. I just changed mine a couple of days ago for this.