A bad thermostat in the cooling system of your 2002 Kia Spectra can cause engine performance problems and even serious damage to engine components. The thermostat is fairly accessible and well within the skills of the average Spectra owner with a minimum of car maintenance experience. And, since this repair job requires a few common tools you might already own, you can install the new unit in your driveway.
Open the hood of your Spectra and disconnect the battery ground (black) cable with a wrench.
Bring a small drain pan and place it under the radiator. Open the radiator drain valve located at the bottom and loosen the radiator cap. After removing about 2 quarts of coolant, close the drain valve and store the removed coolant in a close container for later recycling.
Find the thermostat housing by following the upper radiator hose off the top of the radiator going to the engine. This hose connects to the thermostat housing in the opposite end.
Squeeze the tabs on the clamp that secures the hose to the housing using a pair of slip joint pliers and move the clamp toward the radiator.
Grab the end of the radiator hose at the house fitting. Carefully twist the hose back and forth as you pull the hose off the housing. Absorb the residual coolant inside the radiator hose with a shop rag and keep the coolant from splashing over the drive belts to prevent premature wear of the belts.
Unfasten and remove the thermostat housing mounting bolts with a ratchet, short ratchet extension and socket. Grab the housing and carefully separate it from its mounting base so that you can see the thermostat mounting position. Note how the small jiggle valve on the thermostat points to the 12 o'clock position. Remove the housing, thermostat and gasket from the engine.
Wipe clean the mating surface on the engine and under the thermostat housing with a soft wire brush and a rag.
Install a new thermostat gasket on the engine mounting base and position the new thermostat with the jiggle valve in the 12 o'clock position.
Replace the thermostat housing and thread the mounting bolts finger tight. Tighten the mounting bolts to 19 foot-pounds (26 Nm) using a torque wrench, short ratchet extension and socket.
Reinstall the upper radiator hose to the thermostat housing and secure it with the clamp using the slip joint pliers.
Replace the coolant you removed with a 50/50 mixture of new antifreeze and distilled water. Pour the new coolant through the radiator neck with a small funnel.
Start the engine and watch for leaks around the thermostat housing. When you see the coolant starting to flow through the radiator neck, turn off the engine. Add more new coolant to the radiator to bring the level up to the bottom of the radiator neck and replace the radiator cap.
Add coolant to the reservoir to bring the level up to the "Full" mark. Reconnect the battery ground (black) cable with the wrench and close the hood.
