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Discussion Starter #1
Will a 87-89 NA afm work on a SC? If it will, would a 85-86 work if you
have a air filter adapter. I have a 89SC with the factory air filter set up.
Also when testing a different afm , will it run right with out the air filter
hooked up.
Thanks
 

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I think the voltage signal readings are backward, one reads from + to - the other reads the opposite way and the connector wiring is also different.
 

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Discussion Starter #5
How can I tell if I how the correct one?
I just got my 89sc and it has some issues.
The afm is not bolted down and it don't seem
to have the correct brackets on it.
When I first start it, it does not want to run right
until it warms up. once warmed up it runs
great. I don't have the air filter housing
connected. But I have not been driving it like that.
Any info or tips would be appreciated.

Thanks
 

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Well you need a book for your car I just order an 89 BGB book and the electrical wire book for $100

If you don?t have that you will have to ask someone for the information about how to check the AFM

Basically you take a multimeter and check the resistance values of the AFM and compare them to what the SC AFM should read

More then likely the difference between the two setups (NA AFM and SC AFMs) has to do with the voltage levels and components inside the ECU

The 20V and now I guess the SC AFMs use a 5V ECU (no sure but I think so)
That means the input voltage is stepped down and almost all the components use a 5V signal (TPS, AFM whatever)

Now the NA AFM uses a 12 volt system but the book says 6 to 10 volt input into the AFM output can be 5 to 10 volts

As long as the input voltage doesn?t go too far over the 5v limit it will run but if it spikes to 10v or higher it can mess up the ECU

So I would not go blasting through the gears until you know

Another way would be to check the PNs of the AFMs
But that would be too easy ha ha


davegt27
 

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AFM part numbers

22250-16020 for the NA from 85-86

22250-16040 for the NA from 87-89
22250-16090 for the SC from 88-89
 

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davegt27,
the reference voltage to the AFM comes from the ECU regardless of which AFM you use.

igoatwo2,
to me it doesn't sound like you don't have an AFM problem but more like a vacuum leak somewhere, check the AC idle up hose if the housing and piping have been removed.
 

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davegt27,
the reference voltage to the AFM comes from the ECU regardless of which AFM you use. Both AFMs are similar but are wired differently internally.

i thought i said that it just took half a page ha ha


Davegt27
 

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^^ I got it now, but what I'm saying is that it doesn't matter what the working voltage is, both can be used if they're rewired since they both process whatever the ECU sends them anyway. Now the NA AFM has a connection for the fuel pump relay and I don't think the SC one does. But I could be wrong on thet cause I haven't looked at the wiring since I removed my SMT-6 a while back.
 

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papo j i see my screw up

As long as the input voltage doesn?t go too far over the 5v limit it will run but if it spikes to 10v or higher it can mess up the ECU
i ment the input to the ECU can not exceed the 5 volt limit

and of course it wont since he has a SC ECU

i was jumping back and forth between two ECU's


sorry
davegt27
 

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Discussion Starter #12
I took my AFM off, and it has the part # for an 87-89 NA.
I have just got this car. It don't run good until it warms up.
Once it warm it run's & idles great. I know I should find one
for a SC. But what issues should I have running the NA AFM?
 

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Discussion Starter #14
It has the na afm. I just noticed that it has a extra piece of hose
attached to the intake hose so that the na afm will fit. The SC afm
must have a smaller outlet. Also is the SC afm longer?
The plug in connector does not look like it has been changed.
The wires are not spliced. Does the NA and SC have the same plug?
I guess I need to find me a SC AFM. I will post a thread in the parts
wanted section. I am new to th SC. I have had a 86 NA for over 10
years. Any info on this problem would appreciated.
 

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Papo J said:
It should not even run it it has an NA AFM, those are wired completely different.
^^ When I swapped the GZE into my 88, I mistakenly installed a NA AFM. The car would run; very poorly. Seemed like it was dumping in way too much gas.
 

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Discussion Starter #17
I see on the wiring diagrams that the wires are different,but
is the plug the same? I have not checked the color of
wires on my plug, or how many they are. Am I right, that
the NA AFM has 7 wires and the SC AFM has 6?
 

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if i use a JDM 4AGZE ECU (from AW11) will it work with USDM 4AGZE Harness (AW11)

or will i need to change the AFM too?

and if i do this, will I be able to run the SAFC?

 
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