AFM settings and testing

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matt77
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AFM settings and testing

Post by matt77 »

I came across a thread yesterday about the screw on top of the air flow meter. That thread said that the screw should be adjusted to a depth equal to the number stamped on the housing, plus 10mm.
Well mine is about 12mm deep. The number on the housing looks like 83, so can anyone confirm I need to screw it in to 18.3mm?
What effect would it have that it seems to be out too far?

While I had the AFM off the car I decided to test it using the procedure in the BGB. The PDF of the BGB I am using contradicts itself. Could anybody please point me toward the correct testing method?
4ndee
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Re: AFM settings and testing

Post by 4ndee »

Yes 83 is 18.3mm

It adjusts the fuel mixture not the idle.

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Peter Gidden
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Re: AFM settings and testing

Post by Peter Gidden »

4ndee wrote:It adjusts the fuel mixture not the idle.


It adjusts the fuel mixture AT idle.

Corrected for you :wink:
4ndee
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Re: AFM settings and testing

Post by 4ndee »

Cheers mate :thumleft:
matt77
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Re: AFM settings and testing

Post by matt77 »

Thanks. Probably won't affect my emissions or much else then if it only affects idling.
GreddyMR2
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Re: AFM settings and testing

Post by GreddyMR2 »

I have a number 82 on my AFM and the screw is 1.8cm deep. But for a safety reason, I think, I would like to run richer.
The question is, do I need to screw it down to run richer or up? Although, do you suggest to keep it as is?
And how much to turn it, if any?

Ah, and one more thing that I think could be caused by lean mixture: When I accelerate to 6k or so and change a gear fast and then again push a throttle to the floor, my car struggles for a second and then goes. Or could it be caused by loose AFM(shame it's still not attached securely and it wobbles)?
Steve-O 2007
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Re: AFM settings and testing

Post by Steve-O 2007 »

GreddyMR2 wrote:I have a number 82 on my AFM and the screw is 1.8cm deep. But for a safety reason, I think, I would like to run richer.
The question is, do I need to screw it down to run richer or up? Although, do you suggest to keep it as is?
And how much to turn it, if any?

Ah, and one more thing that I think could be caused by lean mixture: When I accelerate to 6k or so and change a gear fast and then again push a throttle to the floor, my car struggles for a second and then goes. Or could it be caused by loose AFM(shame it's still not attached securely and it wobbles)?


You dont want to run richer, stock is rich anyway...

What Ron Fuel are you using??

Are you running a Dump valve??
GreddyMR2
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Re: AFM settings and testing

Post by GreddyMR2 »

I was running 95RON, but now I filled a tank with 98. Could it be a problem?
With 98 I did not try to push it hard.

Dump valve is stock.
Last edited by GreddyMR2 on Thu Apr 05, 2012 1:57 pm, edited 1 time in total.
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Peter Gidden
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Re: AFM settings and testing

Post by Peter Gidden »

GreddyMR2 wrote:I was running 95RON, but now I filled a tank with 98. Could it be a problem?


Octane rating of fuel will have no effect whatsoever.
GreddyMR2
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Re: AFM settings and testing

Post by GreddyMR2 »

Peter Gidden - SBITS wrote:
GreddyMR2 wrote:I was running 95RON, but now I filled a tank with 98. Could it be a problem?


Octane rating of fuel will have no effect whatsoever.


Then what could effect that?
Steve-O 2007
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Re: AFM settings and testing

Post by Steve-O 2007 »

Peter Gidden - SBITS wrote:
GreddyMR2 wrote:I was running 95RON, but now I filled a tank with 98. Could it be a problem?


Octane rating of fuel will have no effect whatsoever.


Are you sure? I always thought low octane was the cause of bad running when giving it beans due to knock etc..
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Peter Gidden
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Re: AFM settings and testing

Post by Peter Gidden »

Steve-O 2007 wrote:
Peter Gidden - SBITS wrote:
GreddyMR2 wrote:I was running 95RON, but now I filled a tank with 98. Could it be a problem?


Octane rating of fuel will have no effect whatsoever.


Are you sure? I always thought low octane was the cause of bad running when giving it beans due to knock etc..


Octane helps prevent knock.

Customer not reporting a problem with knock.
GreddyMR2
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Re: AFM settings and testing

Post by GreddyMR2 »

Well, I should say I don't see a big difference (if any) running on 95 or 98 fuel...

EDIT: that is probably because I use USDM ECU at the moment.
pistol pete
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Re: AFM settings and testing

Post by pistol pete »

thread revival

sorry my engine has been in so many car i want to make sure mine is correct..

where is the number stamped?
on the top of the air mass meter i can see the part number on the label and them under neath it is
11L then a space and long number

so is mine supposed to be 11.1mm from the top of the hole?
or is it somewhere else?

thanks :)

and from reading this only adjusts its idle mix nothing to do when its running..

thanks
pistol pete
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Re: AFM settings and testing

Post by pistol pete »

found it..
http://www.mr2oc.co.uk/know-your-2-know ... bartid=270

i can check it tomorrow now happy days
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