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Re: Warmup Ignition Retard

Posted: Fri Jan 23, 2015 8:56 am
by Gernby
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?

Re: Throttle vs Airflow table

Posted: Mon Jan 26, 2015 12:04 am
by Hondata
I do not think so.

Re: Throttle vs Airflow table

Posted: Fri Sep 11, 2015 8:59 pm
by shind3
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.

Re: Throttle vs Airflow table

Posted: Thu Jul 20, 2017 6:52 am
by imstimpy
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?

Re: Throttle vs Airflow table

Posted: Thu Jul 20, 2017 7:54 am
by Gernby
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.

Re: Throttle vs Airflow table

Posted: Fri Jul 21, 2017 11:19 am
by imstimpy
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?