my low coolant light keeps going off. im dead positive that it isnt low. what sensor set it off?

 

I would say that if your coolant is up to level, then the sensor itself is going out. It is below the rad cap.

 

The sensor gunks up; take it off and clean it well...if that doesn't work, replace it. It's easy to get to when you remove the battery. It's got a spring clip that slides off to remove the sensor. Be sure to drain your radiator first and don't forget to burp the radiator when you refill it.