I am 99% certain the high pitch sound you are hearing is the fuel pump. That is normal. My '87 930 makes the same noise. The joys of CIS!

ah, great. i thought so-thanks for the insight.

Its the whine of the CDI module. Is it coming from your speakers?

Yes, I should have just said that the sound is normal instead of saying it is the pump. But thanks for correcting me as to the CDI. I just know that the sound is normal and nothing to worry about.

what is the CDI? i'm almost 100% sure it was coming from my back speakers when they were hooked up as i lifted the speaker out and held it to my ear...but once disconnected, the sound could be traced to the engine bay. kinda strange.

by the way, what book should i pick up to learn more about the CIS?

It's Capacitor Discharge Ignition (CDI)

EDIT: I think there are some good books out there. Do a search here and I bet you'll find TONS of info. I would like to learn more about CIS also.