Need some help here. Vehicle is 2002 Chrysler Voyager 3.3l v6 with 130k miles. I've got an intermittent noise coming from the front accessory drive. It's not a squealing belt noise more of a "wah wah wah". And it's not consistent. A/C on doesn't trigger it. It seems to start at random.
Last weekend, I pulled the plastic cover off and ran it, but I couldn't get it to make the noise. I pulled the belt and rotated all the pullies and they all felt okay to me. Nothing rough or wobbly. The water pump had some drag on it, which I think is normal.

One possibility is the alternator- supposedly it has a clutch that can go bad. Maybe it's making noise when electrical load is high? Not sure how to diagnose this.

What else should I look at and how do I diagnose it?

-Dave

All I can tell you is that I had a noise in my 2001 with a 3.8 that drove me crazy over a 20,000 mile period. I changed idler pulley, AC clutch, etc. Finally the alternator locked up. It was the alternator all along. When finally failed and hot the alternator prevented the engine from turning over. When cold and you spun the pulley, you would swear that the bearing was fine. Go figure.......

i'm betting on alternator bearing or clutch as well.
too bad you are across the country, as i have an alternator here you could try.

GOOD KNOWLEDGE from oleHam2.... aka the carrotvanMAN

its the alt clutch / pulley, they sell it , it's called a decoupler. you don't need to buy a whole alt. we change them often in our shop.

Thanks for the advice. I'll get the alternator pulled and check that out.
Is there a way to get the pulley off without the special tools?

there is a special tool. it's used with a 1/2" ratchet, and it is a nut affair on a shaft with a ??mm male hex end that is inserted into the female hex of the pulley/clutch assembly.
it basically locks the assembly up so you can remove/install using the ratchet to remove the hex retaining bolt.
some guys just use an air gun to zip it off and install it, using a hex key [allen wrench] socket.
i have removed bad ones this way, but i can't say if installing one this way does any damage to the clutch or alternator.

Yep, replaced ours on our '07. I only knew for sure as I work part-time @ Advance, seen and heard a number of them. Like the leanburn, great idea but not executed properly (clutch in alternator)

Oh, turning on the a/c or the rear window defroster would trigger it as well