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AFM Post – My current RX is running a ‘flap type’ AFM. Previous EA82T’s I have owned have been the ‘hot wire type’ AFM’s. I have heard that the hot wire AFM are the better and more accurate AFM. Therefore I am thinking that I am wanting to change the AFM around the same time of the conversion.

It is at this point where I then have 2 different ideas.
1) Just do the conversion and do not worry about changing the AFM.

2) While doing the conversion at the same time convert the AFM. However it is at this point that thinking/questions arise again, like can a flap ecu/loom etc run a hot wire AFM? I have the hot wire AFM and for what it is worth I have access to an RX dash that was running a hot wire AMF if they are any difference between the 2 dash’s.

I am still researching this however any addition info on this would be greatly appreciated.
Thanks.

just abit of ea info.the flapper[3 plug ecu] and the hotwire[4 plug ecu] ran the same engine sensors/plugs except the 4 plug has a extra pollution style sensor[it don't matter] and afm plugs i think were different.to get the hotwire to work you need the 4 plug ecu.Now i seem to recall someone converting a hotwire to flap by picking out the wires at the ecu plugs so i'm guessing you could go the other way.also a l engine loom is way easy to strip down to engine only and splice in.
oh yeah the mpfi dashes are the same evn the non turbo dash has the circuit for turbo light etc.

I was under the impression that flapper and hotwire afm's had a different range of voltages for their output
cos, the hot wire uses a heated piece of wire and uses the change of its temp, combined with the reference of the air temp, to calculate the amount of air flow.
the flapper is just a poteniometer connected to a flap that moves with the mass of air that is flowing through the pipe.

You could try, but i dont think its practical.


Gannon

Suparoo wrote:I was under the impression that flapper and hotwire afm's had a different range of voltages for their output
cos, the hot wire uses a heated piece of wire and uses the change of its temp, combined with the reference of the air temp, to calculate the amount of air flow.
the flapper is just a poteniometer connected to a flap that moves with the mass of air that is flowing through the pipe.

You could try, but i dont think its practical.


Gannon

Yes agree'ed, they do have similar outputs. Hotwire is a 5.0V WOT output, and the flapper is also 1-5V, but wiring is different.
Hotwire suffers from calibration problems as they get older, and especially when dirty. Same prob with early EJ20 AFMs as they are similar.
The Flapper is considered more robust and reliable, but cruder and simpler in operation. I would stick with that one if thats whats in there Craig.

Points taken - pondering...