2002 Cougar Problem...Please Help

I own a 2002 Cougar V6 and lately i've been having an irritating problem. When my car is idle it starts bucking (I think is the best way to describe it) and appears to be losing power...Ex..the rpms rev up and down, my lights go dim then bright again, my car makes a whinning noise, and it only seems to do this while idling. It's still driving ok. any ideas on what it may be? I was thinking my altenator but no lights or anything is comming on...yet.

could you explain the whinning noise?

if it is a strange deep amlost horn type sound i would say it is your iacv(idle air control valve) this can cause your car to not hold RPM's when idleing.