New Tuning Tutorial: WeathermanShawn

[joecar]

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if your OS doesn't have DYNAIRTMP_DMA, then you can approximate it using 0.85*ECT+0.15*IAT or by looking up the temperature blend table.

Joe, what's the basis for this estimator?

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How close is that formula to the pid? Can someone do a quick comparison between the two and see how close the net values are?

It was late last night when I typed that... <- me slapping upside my head 4x

Sorry, I had meant to type this: 0.85*IAT+0.15*ECT

i.e. it should biased toward IAT.

I intended that as a simple estimation, exactly what Shawn guessed I was doing...

I say this from looking at B4901 and from observing DYNAIRTMP_DMA say when VSS > 30 mph in various logs...
I should have instead said to study B4901 for your airflow range, which brings us to the next point:

A more accurate way to do this is to do a lookup of the B4901 values as suggested by mr.prick earlier in this thread...
and this is exactly what Ninety8C5 did: showpost.php?p=118165&postcount=29

[ but this still doesn't factor in B4902 ]