This little guy actually measures the amount of unburned oxygen leaving your engine. It’s constantly sending that information back to the car’s computer – the engine control unit or ECU. The ECU then uses that data to adjust the fuel mixture, making sure the engine runs as efficiently as possible. There are usually multiple oxygen sensors in a vehicle—one before the catalytic converter and then one or more after it. They all work together to keep things running right. Think of it like this – it's the engine’s way of “tasting” the exhaust. It tells the computer if the mixture is too rich (too much fuel) or too lean (not enough fuel). The computer uses that feedback to fine – tune everything. It plays a big part in controlling emissions and making sure you get the best possible gas mileage. It basically ensures your engine is breathing correctly. A failing oxygen sensor can really mess things up. You’ll notice if it’s gone bad because your check engine light will probably come on. More importantly, it can cause your car to run poorly—maybe rough idling, decreased acceleration, or really noticeable drop in fuel economy. Left unchecked, it can even damage your catalytic converter, which is a much more expensive repair. We carry a lot of these, and you can find a good selection at Fixparts Online if you want to browse. It’s one of those parts that’s relatively inexpensive to replace but can save you a lot of headaches down the road. We’re here to help: Sensor (MPN 34526773020) includes a 12-month warranty!

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