Coolant light is on, which sensor to change out?
 

There are two coolant sensors above the thermostat housing. I've cleaned both sensor's terminals, but no joy. The light wasn't coming on until after a few minutes of driving, now it comes on at start-up and stays.

Gas mileage is dropping fast, and exhaust odor is getting bad.

I don't know which of those two coolant sensors I need to change, and the WSM doesn't seem to indicate which one. Any idea?

Thanks.

check the coolant level . And the snder connection on the top of the coolant bottle
Also there is a pressure switch next to the washer tank fill tube. If your losing coolant and its not leaking the you may have a blown headgasket also consider replacing the coolant cap with a new one