I have a 1996 Sonata 2.0 16V and wondering where the thermostat is located and what is involved in replacing it

 

Follow the upper radiator hose to where it attaches to the engine to find the fitting. Unplug the temperature sensor, disconnect the hose and remove the two bolts that secure the fitting to the engine. Pry the fitting off and you will have found the thermostat. Be sure to install the new thermostat in the same orientation and be sure to use a new gasket. I usually smear a thin coating of RPV silicon sealant (a little goes a long way) onto the gasket. Be careful to not over tighten the bolts and strip the threads.

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