stupid ? but what is it?

are you in the process of doing a swap? if so what gen.

a afm basically replaces the map sensor. it reads air coming in and its density and its temperture.

1st gen 3sgte swap.I have a mr2 map sensor thats for vacum.

The AFM is the silver and black thing that my air filter is attached to in that photo.

in canada we call that a mass air flow.I got one and its out of a rx7 and it works.My buddy has a 3sgte mr2 and thats what he used!Its also bigger than the one in the 3sgte.It gets more air volume.

Im still not getting any spark.I have to check if the igniter has a ground because I know it has 12v.

AFM would be the better name for it, although AFM and MAF are essentially the same thing, there are newer MAFs that are completely different. I'd suggest you try swapping out the AFM. Even with everything perfect... a bad AFM will cause no spark. Try swapping one from a Toyota car... a 22RE AFM or 4AG AFM or 7MG or something. The engine may or may not run good with those AFMs... but if it sparks and studders and tries to start... you'll at least know what's the problem. I don't reccomend crossing different AFM types because they are different. The flaps send different signals, read out different voltages, etc... they are not universal sensors. I fried 2 smallport 4AG AFMs (US/CANADA Spec) running on my smallport 4AG with bigport harness and ecu.

all denso air flow meters are the same they only bring in more or less air.Thats all.toyota denso and mazda denso ford denso is all the same.

The afm that I have I tested out of a celica 3sgte book and made sure that all the voltage and all the resistance was correct and it was!The only real differance is the pinouts 5 pin, 7 pin etc

on the 3sgte the map sensor is also known as the turbo pressure sensor. it does 2 things...1 tells the stock boost gauge and the ecu how much boost the car is seeing, 2 ...sends a signnal to the ecu to fuel cut if the car over boosts.

the AFM measures the amount of air going into the engine. this is where the ecu gets its readings for a correct air to fuel ratio. many mr2 guys report the rx7 afm to be the same part, tho i cant say i really know anyone who has it installed on their car.