squeaking noise on '88 80Q

[Oleg Rekutin]

'88 80 Quattro 227k.

Two videos: when running cold, almost no squeaking noise, but you can
start hearing it:

http://www.youtube.com/watch?v=H1vAmZYXce8

Idling warm, much more pronounced squeaking noise:

http://www.youtube.com/watch?v=VHUml_wfMlA

When the engine is revved to 1500 RPM or so, the squeal/squeak goes
away. It comes back when the RPMs return to idle.

What could that noise be? Is this a pulley on an accessory belt of some
kind? Or is this a major engine issue?

Also, what's that clicking noise (easily heard in the "cold idle"
video)?


Thanks!
- Oleg