Purchased a new (to me) 92 745. Absolutely have been happy with my purchase. However, I am running abnormally hot when idling and driving extremely slow.

First time I noticed was about a week ago when I was viewing a new area and driving about 5 - 10 mph. Was not too bad, about 3/4 just enough to get my attention. It actually went down after getting back on the road though..
Second time was a few days ago when I kept car running while waiting for the old lady to get out of the store. Maybe 15min? And it actually went all the way into the red before I realized it!
Today, this happened again while waiting in a drive thru line.. Got just about into the red..

What in the world can cause this?! I do not have a single issue when driving at a normal pace. And, even when idling.. The car does NOT idle rough.. Just heats up significantly..

 

Check your electric fan to see if its operating. When the car is not moving the electric fan is the only way to cool the radiator.

 

That was my first guess too.
Turns out its the water pump. Nearly **** my britches because at first glance it looked like the head gasket was leaking. Nope, water pump!
Guess I'll go ahead and get that replaced and the belts too while I'm at it.