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Old 09-16-2011, 03:34 PM   #1
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Default Coolant corrected air density: Because I'm dense.

Here is what this is set to now. I have never touched this, so this is how it was when I got the MS over a year ago.
After searching a little bit over the past several weeks, I still don't know what I'm supposed to be doing with this. However, I think my settings are completely wrong. This is an uneducated guess.

I have not noticed a change in AFRs in boost, but then again, the temperature around here lately hasn't really fluctuated much. I tuned fuel in this weather. Winter is on its way though, so I wanna get this fixed (if its even wrong) before it starts dropping into the 40s here (inb4 40 is not winter). My cold idle is lean, which I understand is a common issue.

I'm worried that with this correction set to turn off at over 3000 rpm, that my high load AFRs may fluctuate into dangerously lean areas. Or not, I don't know, I still don't understand how this table works in relation to IAT vs AFR. I've also read to turn the air density correction to "normal". No idea what that is doing.

What the hell do I do with this table? I'm more worried about my AFRs in boost changing when the weather gets cold/hot.
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Old 09-16-2011, 03:41 PM   #2
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The firmware has hardcode Ideal Gas Law code built in. We have found it's highly agressive, that table actually negates the code so your gAir should remain 100% through the temperature range. This give you a way to prevent lean hot starts from the code seeing really high heatsoaked AIT sensor temps.

outside the correction range shouldn't really change if your fuel table is tuned well, the gas law is the law, especially if your AITs are in the 50-100F window. You can see the code is fairly linear based on temp.

the problem that us with MS2 or MS3 are having is that there is no way to end corrections and we acutally WANT that feature back. So we can dela with heatsoak and allow the ideal code to do its thing under normal conditions.
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Old 09-16-2011, 03:43 PM   #3
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So you're saying the way my table is setup is a bypass to all the IAT heatsoak/AFR fluctuation issues people are having by ignoring the aggressive code in the firmware?

FWIW I still run a little lean on hot restarts
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Old 09-16-2011, 03:47 PM   #4
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basically. if you are still going lean, you can increase the correction at the 100F row.

The ability to end corrections is great in boost, since you'll quickly jack the AITs back up and you don't want it to dump all the extra fuel in on top of your normal ve%.
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Old 09-16-2011, 03:56 PM   #5
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Mind blown. I'll drive around later and see if my Gair actually stays at 100%.
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Old 09-16-2011, 04:27 PM   #6
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Quote:
Originally Posted by Braineack View Post
the problem that us with MS2 or MS3 are having is that there is no way to end corrections and we acutally WANT that feature back. So we can dela with heatsoak and allow the ideal code to do its thing under normal conditions.
Shameless plug: I've corrected this in the MS2 ECUs I build.

Custom firmware modifications
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