What is an O2 Sensor?

What is an oxygen sensor? Welcome to Mercie J auto care, where compassion and craftsmanship come together. I'm Rick Smith, master certified technician. Well an oxygen sensor or an O2 sensor, basically what it does is it screws into the exhaust. So there’s a piece of an exhaust and it screws in here and I don’t know if you can see it sticking through but regardless, this is what it looks like. What it does is it measures the difference in oxygen from outside of the exhaust and from the inside of the exhaust. The computer then uses that data to determine air fuel ratios and whether it needs to add fuel or reduce it. It will also figure out whether the catalytic converter’s working or not. Now that’s a general term, oxygen sensor or O2 sensor. They can also be called air fuel ratio sensors. They’re a little bit different in exactly how they work, but they all basically do the same thing. They tell the computer what the fuel mixture is. So that’s what an oxygen sensor or 02 sensor or air fuel ratio sensor is. I hope this has been informational to you. Until next time, safe travels and blessings to you.