How do you replace an Oxygen Sensor on a 2000 Daewoo Nubira?

There are two sensors on the nubria, one under the engine cover, the other under the passenger side connected to the exhast. You can see the first one sticking out in front of your engine under the cover and the second one under the car, there easy to find. You'll need a special O2 sensor socket to take them out, it has a gap down the side so you don't mess up the wires. Any Autostore will have them for purcase or loan (if you put down some money you can return it).