3.5 Aurora Low Pressure error messege

I have an 01 3.5 aurora with little over 100k miles on it and when i first start the car a "low oil pressure" light comes on. now when im on the oil pressure selection it goes from 0-130 psi in an instant... jumps back and forth.. when it is warmed up the light goes away. ive heard something about the harmonic balancer and such, just never tryd it.. any suggestions?



thanks

Sounds more like an oil pressure sensor malfunction.