1997 Chevrolet Lumina

Engine Cooling problem
1997 Chevy Lumina 6 cyl Front Wheel Drive Automatic 80.000 miles

Engine runs fine and cool while driving, when I get in traffic or im idle a lot I see the coolant temp climb up, it never gets HOT but I guess it would in the dead of summer on a 100 degree day. When I start traveling again the temp comes down to a lower point. I have full and clean radiator, and I dont think the fans are coming on. I never hear them kick on and I watched to see and I dont see them come on. What do I check or what could be the cause of the fans not coming on?
January 10, 2009.

Hi: Here is how they work. The temp sending unit sends a signal to the fan relay when a certain temp is met. Then, the relay sends power to the fan. When the engine temp is toward the hot area, disconnect the fans to see if there is power to them. If there is, the fan motor must be bad. If there is no power, you need to work your way backwards to see where you find power again. Let me know what you find.