The thermostat is a component of your car engine that is very important, yet rarely thought about. When the thermostat fails, it will be stuck in either the open position or closed. If it is in the open position, your engine will never heat properly, and your heater will not work. If it is stuck in the closed position, heat is never released from the engine and your automobile will overheat quickly. With the 1997 Chevy Lumina being over a decade old, it is reaching a point where many of them need to have the thermostat replaced--which means you need to know where to find it.
Open the hood of your Chevy Lumina. Under the driver's side dash, near the door, is a hood release lever. Pull this lever to unlock the hood of the car. Exit the car and walk to the front of the hood, where a lever will allow you to open the hood, somewhat like opening a car door.
Locate the radiator hose. This is a large black hose that connects to the radiator at the front of the car, under the hood. Trace the hose from the radiator back to where it joins the engine block on your 1997 Chevy Lumina.
Find the throttle body. This is found near where the radiator hose joins the engine block, on the driver's side of your Lumina. Once you have located the throttle, look just below that area to see the thermostat.
