ISV & rpm fluctuations

[SHOWMX@aol.com]

First off, I have used the search engine for info regarding this and many
other subjects and have found it to be a long, tedious,  procedure sometimes
producing a little bit of info.  Anybody else frustrated w/search engine?

The reason I have brought this up is because I  feel guilty asking questions
about subjects which have been previously discussed.....So, if people are
reluctant to answer my ocassional questions, I'll understand since I don't
have much BTDT experience to contribute to the board.

Anyways on to the questions:  When I turn on headlights, heater, rear
defroster, and heated seats or any combination of these, the idle in my 4k
drops aprox 250rpm.  Is this normal?  I thought the ISV's job is to maintain
consistent idle under these type of conditions.  When all electrics are off
and I observe the idle, it is constant and normal. Upon unpluging the ISV, the
idle surges up aprox 500-750 rpm higher than set idle speed.  Normal...???  I
have read posts regarding cleaning the ISV, maybe this is in order? Test
procedures...?

BTW, I think Santa is bringing me a Bentley manual for X-mas!  I hope so, yet
I know the q-listers wealth of knowledge is just as valuable of a  resource,
if not more.

Thanks,
Briand P.
'87 4kcs