There is so much nebulous and contradicting information out there. I have seen these terms used interchangeably and then elsewhere differentiated.

ARE these, in fact, the same thing (which I doubt)? And if not, where is the AFR Sensor located on an 07 Fit Sport w/auto?

 

Air -fuel sensor is located in manifold.


Instead of changing voltage (like O2 sensort does) it changes the current flow amount and direction in response to mixture changes

 

basically, yes, they are the same... but

there are narrow-band and wide-band sensors - if you are installing an afr gauge you certainly want a wide-band which will allow you to see a full sweep of ratios. Narrow-bands are typically used as o2 sensors in oem applications as a cost-saving measure (although, the front fit sensor is a wide-band).

the sensors that are used in oem applications are used to tell the computer how to adjust the fuel mix and timing advance... an afr gauge shows you what the mix is and that's about it (unless you have it wired to an aftermarket ecu). you want an afr gauge when you are mixing the fuel and adjusting the timing yourself to be able to see what's actually happening with the adjustments you make.

hope this helps.

 

Many just call all of the sensors an Oxygen sensor, until it comes time to be more exact. Most everyone knows what an O2 sensor is now, but AF sensors are still relatively new and not all understand the differences, nor why the different sensors may be used.

An AF sensor and an O2 sensor might look physically similar and do similar jobs, be installed in the exhaust system like usual.......BUT

Their internal construction and operation are completely different and accuracy is incredibly different, and a PCM/ECM can only make use of the sensor type(s) it was designed to use.
You cannot swap one sensor type for the other and expect it to work correctly.

An AF sensor (narrow or wide band) can provide very accurate mixture ratio information throughout a broad range, but plain O2 sensor can only discern if the mixture ratio (oxygen content) crosses above or below a certain threshold.




The AF sensor is located PRE-CAT. In that car it's in the bottom of the exh manifold.