I bet no one really has this question, what is the difference between an AFM (air flow meter) and MAF (mass air flow). In case you did wonder, here is the answer:

MAF: mass air flow sensor, located before the air filter on the air intake. It measures the amount of air flow controlling the air/fuel ratio.

AFM: The air flow meter measures the intake air flow rate by measuring a part of the entire flow. Measurements are made in such a way that the ECU receives electrical output signals varied by the amount of heat emitting from the hot film placed in the stream of the intake air. When intake air flows into the intake manifold through a route around the hot film, the heat generated from the hot film is taken away by the air. The amount of heat reduction depends on the air flow. ...

I believe AFM uses rate to measure air, and MAF uses vacuum or something like that.. Import vehicles typically use AFM and domestic’s such as Ford/Chevy/GMC use MAF as well.

Going off of this information, I would say that the Mazda, being an import, would use an AFM, which is a sensor on the accordian hose before going into the intake manifold. Please correct if wrong.

 

yeah we should have the AFM cuz you cant setup an air filter properly (trust me) i learned that the hard way but im too lazy to take it out

 

actually the mazda 3 has the MAF Sensor. i know nothing about an AFM Sensor being on the 3.

 

interesting, where is the sensor located and what size is it. what i would like to know as well is the size of intake hose, where it connects with the stock air box, does anyone know that? also, looking in the manual, there is a fuse for the AFM, but nothing is listed for an MAF.

 

yeah id like to know where the fudge its at also.

 

AFM and MAF are interchangeable terms. They both do the same thing. Different auto mfgs. use different termanology. Example, Mazda uses ISC which means Idle Speed Contol and GM uses IAC which means Idle Air Control...they both do the same job. When you were saying that one of the terms you used work off vacuum, they both do. The engine creates a vacuum no matter what when it is running. The modern MAF works off the hot wire sensor and the older ones work off a spring loaded door that opens wider when the throttle is opened up more.

 

ok, on top of the air box, there is a sensor that is screwed in to the top of the box with a long piece going inside. what exactly is that?

 

the air sensor,right? w/o the car wont run.

 

I am going to assume thats what it is, so in a CAI, there has to be a place for that to plug back in, and someone cannot just remove the box and replace with a cone filter. so there goes that idea.

 

actually thats exactly what i did