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The 20.9 Percent Factor (Oxygen Sensor)

Do you know what gas makes up 20.9% of the air we breathe? 

It’s oxygen. Oxygen is an important part of the combustion process that enables your engine to make power. The amount of oxygen in the exhaust provides clues as to how well your engine is running. Your vehicle has oxygen sensors that provide the engine computer with the information it needs to adjust the combustion process.

Multiple Oxygen Sensors to Identify Multiple Potential Problems

Many vehicles have more than one oxygen sensor. They are positioned in the exhaust system, one between the engine and the catalytic converter, and another after the catalytic converter. An onboard computer compares the oxygen levels before and after the catalytic converter to determine if the converter is working properly.

An oxygen sensor may fail for many reasons. You could have bad fuel that contaminated it. Your sensor may have simply worn out. 

Your engine may be burning oil, and that soot can ruin the sensor. Road contaminants, like salt and water, can corrode the sensor.

Signs your Oxygen Sensor Could be Going Bad

There are signs that your oxygen sensors may be going bad. You may see your Check Engine or other warning lights illuminated. A trained technician at your All Pro Servicenter can retrieve a diagnostic code generated by your engine computer. 

Another sign is that your engine may be running rough. If you spot black, sooty smoke coming out of the tailpipe or notice your fuel economy has plunged, that could be a sign. Also, beware of blue smoke or other exhaust gasses.

If you see any of these signs, head on over to your All Pro Servicenter. They have the equipment and training to track down the problem. Simply replacing the oxygen sensor is often not enough; the technician will have to get to the root of what’s causing the sensor to fail and repair that as well.

That gas that makes up 20.9% of the air could hold the key to your vehicle running at 100%. Make sure your oxygen sensors are working the way they should.

Beyond Oxygen Sensors

At All Pro Servicenter, our technicians are equipped to handle issues caused by everything from high mileage to issues with engine control. We can identify issues within the combustion chamber, identify root causes of engine misfires, oil leaks, high oil consumption, figure out why your car is burning oil, and more. From piston rings, ignition coils, and plug wires to spark plugs, we have you covered. Our diagnostics tools are coded with all of the latest trouble codes to help us provide exhaust tips


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West Des Moines, IA 50265

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