I just by pure coincidence discovered a disconnected plug hanging off the engine harness over the starter motor, basically resting on top of the motor. It is about 1" wide, has a metal wire on one (wide) side clearly for locking onto the male part of the connection, and has 3 female contacts in it. I lifted it up and lashed with yellow tape to the kickdown cable just so it doesn't bounce freely in the area between the intake manifold and the starter.

The car runs flawlessly, everything is in working order. I looked and felt around there but cannot figure out where this should connect to and, most importantly, for what purpose?

Sorry for blurry photos from my phone, but here it is:
http://i35.tinypic.com/11jvxmt.jpg
http://i38.tinypic.com/34t1guv.jpg

Thanks in advance!