Mercedes Benz repair: 02 sensor, mercedes 500 sec, oxygen sensor

Question
I have a 1985 mercedes 500 sec and the light for the o2 sensor came on.  What does it do and is it a big deal if its not fixed right away?

Answer
Greetings! Im sorry for your luck!
This will not hurt anything if left on for a little while. It means that the oxygen sensor is tired and will be in need of replacement within a month or two. You may notice a small amount of gas usage and car may run a little different as this goes through the engine computer. But, you will need to fix this somewhere down the road! So save yourself about a hundred dollars to fix this. Thanks and have a great day! Rick