91 calais quad 4 temp light is on??

Hello every1, i am currently driving a 1991 olds cutlass calais sl with the quad 4, ive replaced the water pump, radiator, thermostat, and still cant figure out why the temp light keeps coming on.... could this be some sort of temperature sensor or some sort? any help would be gratefully appreciated!

I would check the wires & plug in for the temp sending unit for breaks/shorts and dirty connection.

Here is a link (http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/0e/56/40/0900823d800e5640.jsp) that will help find & test your Engine Coolant Temperature (ECT) sensor.

hope that helps!