Extra alternator part ?

[Indiana_Red@hotmail.com (Ken B)]

On the back of my 90 A alternator there is another little square black
piece. about 3/4x3/4x1/2 with a little pigtail that plugs in to a small
spade connector.  Looks like some kind nois supressor or something.  This
was on my old one but did not come on the reman I just bought from BowWow.
This new unit was only giving 12.2V but that was w/o this little piece.
Havn't tried it with it on.  Would that be the problem?  I am about to try
and exchange this faulty (?) alt.
Thanks as always
Ken
1979 Scirocco  "McFly"
16v conversion "...it's working....It's WORKING...!"
tracing electrical gremlins now...
VORTEX:  "Indiana Red"