Throttle vs Airflow table

FlashPro questions & answers specific to the 2006-2009 (US, UK, Asia) S2000
Gernby
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Joined: Thu Oct 29, 2009 2:53 pm

Re: Warmup Ignition Retard

Post by Gernby » Fri Jan 23, 2015 8:56 am

What change, if any, might this table cause under normal running conditions? Would it have any impact on throttle tip-in at higher RPM and / or loads?
'06 NFR S2000

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Hondata
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Re: Throttle vs Airflow table

Post by Hondata » Mon Jan 26, 2015 12:04 am

I do not think so.
Hondata

shind3
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Location: Pittsburgh, PA

Re: Throttle vs Airflow table

Post by shind3 » Fri Sep 11, 2015 8:59 pm

Sorry it took me so long to respond to this thread, but I've finally been able to confirm that this table fixed this problem I was experiencing!

I set the "Throttle flow vs opening" table to the following values.
0 76 247 465 679 909 1158 1424 1701 3276

Stock is.
0 31 100 178 264 362 468 587 713 1920


My IGN hovers around 6-7 degrees and the RPM matches the idle speed target perfectly. It would be nice to know the target idle timing and its allowable range so I could tune this so at steady state the IGN sits in the middle of the range right at target IGN.

I'm going to try a straight 100% increase from stock next and I think that will be just as good.

Thank you very much Hondata.

imstimpy
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Joined: Mon Nov 04, 2013 2:04 pm

Re: Throttle vs Airflow table

Post by imstimpy » Thu Jul 20, 2017 6:52 am

The description in the help is for the Throttle flow vs opening table is insufficient: "In some situations the ECU will need to know the air flow past the throttle body for a certain throttle opening."

Can I get an explanation for when the table is active and what effect it has during those conditions? Said another way, if I increase the Flow by 100%, what effect should I expect to see and when should I see it?

Gernby
Posts: 308
Joined: Thu Oct 29, 2009 2:53 pm

Re: Throttle vs Airflow table

Post by Gernby » Thu Jul 20, 2017 7:54 am

This table has a huge impact on idle, and small changes can cause the ECU to throw codes and go into limp mode. The table also seems to be used for lots of other things, depending on how the closed loop throttle and WOT determination values are set.

I've been planning to write a "book" about that table and several others, but haven't gotten around to it. After spending years (literally) tuning my '08 S2000 and '13 Civic Si each with DBW ITB's, while daily driving both (in all types of driving), and getting both of them to pass OBDII emissions testing with just 1 "incomplete" readiness test ... I've found that the Honda ECU actually has the ability to blend TPS and MAP to determine fuel and ignition timing. This table is one of the critical components of that functionality. Some of the other tables critical to that function are the cranking fuel, MAP WOT determination pressure, and TPS WOT determination Low / High.

As I type this, I'm remembering more about this table ...

Changes to the values in the table will also change the default throttle position while decelerating in overrun, which can cause odd DTC's that are difficult to diagnose.
'06 NFR S2000

imstimpy
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Joined: Mon Nov 04, 2013 2:04 pm

Re: Throttle vs Airflow table

Post by imstimpy » Fri Jul 21, 2017 11:19 am

So the table is used at idle, among many other things like overrun, CL/OL transition, and WOT transition. How do changes to this table manifest in idle behavior?

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