Whoosh from belt idler pulley?

[BearZDefect]

Recently I noticed a whoosh sound from my 1997 i30 upon acceleration of the engine. The sound disappears at any steady engine speed that I can bear to listen to with my ears near the engine.

Opened the hood to locate the source. It sounds like it is coming from the accessory belt area. Looking closely, the idler pulley appears to move a bit laterally upon acceleration of the engine.

Belt tension seems fine, and there are no belt squeals.

Does that movement indicate a defective idler? (I suspect yes.)

Could that be the source of the sound?

Where is the bearing for this pulley? Is it part of the pulley, as in this pulley?

(If this is the right part I'll replace the accessory belts while I'm at it.)

This is a Nissan VQ30DE engine, manufactured in 1996.

Thanks!

 

[AdRock]

The tensioner is designed to move a little. On pretty much every engine I've seen with that type of tensioner it will move like that when the throttle is punched. it's because the crank suddenly pulls the belt very tight on initialy rpm increase. You could possibly have a tensioner bearing going out though.

 

[BearZDefect]

Thank you, AdRock. Very helpful input.

 

[mechtech2]

Taking the belt off and simply moving it aside allows you to turn , feel, and listen, to every driven component.