what causes the motor to overheat on 1999 Cadillac DeVille

on the freeway cruising 62mph, the car runs fine, however when I slow down the all hell breaks loose and the car overheats. In the the city, the car overheats after 30 minutes driving.

by in Modesto, CA on November 17, 2012
2 answers
ANSWER by , November 17, 2012
Best guess : radiator cooling fans are not working. Ram air at speed will cool rad. but at slower speed fans have to do it.
ANSWER by , November 17, 2012
most likely the cooling fans or its circuit...this vehicle has a complicated cooling fan electric circuit.