Squeaking belt

[Brent_TJ_EasterSubs]

Hey guys,

I've got a relatively new serpentine belt (bout 4 mths?) on my Oct 99 TJ renegade.
Its been squeaking when the engine warms up...!
From what Ive read, if the squeak was just belt wearing in, it should lessen as it warms up, not get worse.

Also, it doesn't squeak while accellerating as much, mainly while idling or coasting.

So I'm wondering if adjusting the belt will help or if this sounds more like a bearing problem to you experts?
The belt tension adjustment looks pretty straightforward for me to try myself (not being mechanically minded very much, referring to the link below for some guidance)
http://www.jeepsunlimited.com/forums...d.php?t=546009

The local mechanic said the tension looks right and was going to order me in a new belt...I'm sceptical this will resolve it since its already a relatively new belt.

Any ideas/feedback?

[Wooders]

Normally if the belt is not tight enough it usually squalls at inital startup.
So I'd be thinking it might be the idler pulley.

[sir_camel]

Best get the idler pulley checked...mine let go at 110kmh on the F3 loosing all accesories. Was pretty scary. Fan belt took out half of the engine bay too!