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Discussion Starter · #1 ·
Hi All,

I have a nismo AFM part number: 22680 RR580 A360-000 J71.
It is currently reading lower than the other one and i was wondering if cleaning it would help get the readings back to the same again ?

Also how do i clean it properly ? do i just spray the sensor with brake cleaner and then let it dry off ?


I think it is currently causing a missfire on my car and after checking all of the sparkplugs, the car is running rich across all cylinders - will 1 AFM reading low voltage cause this ???

Ta,

Peter
 

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WHen are you seeing different airflow values?

At idle?

Rob
 

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Discussion Starter · #3 ·
hi rob,

Yes the values read different at idle..... one is at 0.6mV and the other is at 1.0, there is a difference between the 2 values all the time as far as i can tell.

This is taken from the sensor check section in the power fc ETC menu

However im not sure if this would cause overfuelling ??

The other option could be that i have a faulty ignition amplifier (which i have a replacement on the way) as ive checked the splitfires and iridium plugs which are all ok - from the plugs it looks to be running rich across all cylinders...
 

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try regrounding the ignition amp - sometimes just moving the ground to a different corner does the trick. If not, get a fat car stereo ground wire and ground the thing directly to the battery and see if that helps - give the amp a good solid supply of electrons :)
 

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Are they both Nismo AFMs? AFMs with greater capacity will read lower v than the factory one under the same conditions. If they're both Nismo AFMs then try removing them both and carefully spray brake cleaner down the tube and over the thin wire sensor. No harm in spraying the mesh at each end of the tube to clean it up either :)

Check the condition of the pin connectors then try 'em again.
 

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Discussion Starter · #6 ·
yeah they are both nismo AFM's....

I will spray them later today hopefully as i have alreday removed them from the car. Also will try to run anther ground to the chassis for the ign amp to see if that helps.

Thanks guys :)
 

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Hi Peter,

Are you sure they still read that much different all the way through?

AFM's will often read different values at idle, if you change the percentage on the fuel trim on 3 cylinders (front/back) you will notice that will change .

Rob
 

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Discussion Starter · #8 ·
they move so quick and because the car misfirse i cant hold a steady rpm to see if it is different throughout the revs...

Even if one was lower would this cause the car to run rich ?

I would have thought that if it was reading less air than it was getting that it would be lean instead of rich anyway....

I have already bought another ign amp to try that but if that doesnt fix the misfire then im running out of ideas.

The sparkplugs are black on each one indicating rich fuelling
i have iridium plugs which are all in good knick
also splitfire coils which look to be ok condition

there isnt any hoses off anywhere and the vaccum seems to be ok

Is there anything else i should look for ?
 

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Discussion Starter · #9 ·
i also tried removing each connector to the injectors at idle one at a time and the engine note changed each time i removed one so the injectors seem to be working ok ?
 

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might want to also give this a whirl - disconnect the ignition amp (four screws and two connectors), and then bring it inside and stick it on a table. Give it some love. Reinstall when the ignition amp is quite cold, at least room temp or below through and through.

I've done this twice and for some reason it has worked to solve a general misfire issue.

Can't hurt and it takes about two minutes to put in/pull out that little amp.
 

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It seems to be ignition amp season at the moment mate, ive replaced my own/my best mates and one at work.

Does the missfire seem like an individual cylinder miss or across a few cylinders? ie. is it a single miss every second or so, or a flat missfire (if that makes sense.

YOu may have posted it already mate, if so i have missed it :D

Cheers

Rob
 

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Discussion Starter · #12 ·
i think it might be a couple of cylinders to be honest when its under load.... at idle its probably only one cylinder and occasionally
 
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