Using a Auto Code scanner or scan tool can be a big step in the air quality that we breathe.
Because you can see if an oxygen sensor in your car is starting to be faulty. A defective oxygen sensor can trick your car computer’s to run the car too rich or too poor. Then you can smell unburnt gas coming out of exhaust pipe.
Using a scan tool like the Elmscan5 can make you locate the faulty sensor. Of course you need also a desktop computer or laptop for reading the scan tool’s results. A good scanner will make you do live results with the car running on the road. This is the best way of testing various sensors or fuel injectors on you automobile.
A footnote:the obd2 system is designed to monitor the emissions performance of the engine.You read the oxygen sensor or O2 sensor results like this: the voltage output of the O2 sensor should read minimum 0.1Volts (lean) and maximum 0.9 Volts (rich). A good oxygen sensor should produce an oscillating waveform at idle that makes voltage transitions between 0.1 and 0.9 Volts. A bad sensor could be always stuck at 0.45 Volts . If you look at the output of an oxygen sensor with an oscilloscope with a good sensor, you will see a oscillating waveform (sine wave).With a very good Obd2 scan tool, you see see the graph of the output of the sensor like you were looking at the monitor of an oscilloscope. You must also see the voltage reading of all sensors including the O2 sensors with the smallest delay possible.
In conclusion, if you monitor your car’s emissions performance of the engine. You can replace faulty or near faulty O2 sensors. You will gain performance of the engine because a car run much better with new oxygen sensor. You will burn less full and you will pollute less in our precious atmosphere.
This is from obd tool website technical support: Auto Code Scanner Could Be Good For The Environment