Where is the thermostat and how do you change it on a 2001 Kia Sephia?

The thermostat on a 2001 Kia Sephia is located near the engine, typically at the engine's end where the upper radiator hose connects to the engine block. To change it, first ensure the engine is cool, then drain the coolant, remove the upper radiator hose, and unbolt the thermostat housing. Replace the old thermostat with a new one, ensuring the rubber gasket is in place, and then reassemble everything securely before refilling the coolant.