how to remove air pocket in colling system

if the translucent reservoir is filled to the "full cold" mark, and the dip tube on the cap is in place the system will belch itself~....else a weak waterpump, restricted flow (from prior overheat) or bad coolant could precipitate this condition~

recommend a new temp sender for your fan troubles~

sorry none of those seem to be for the Optima...simply ask at your auto parts store...they'll give you the right one~

Will belch with a clean two way cap, otherwise squeeze fat hoses while idling and cap off, look for bubbles in resover and add coolant as needed