While investigating AZ1G800T (JDM WRX-STI Spec C) and AZ1G800D (SADM WRX) I've found some curious differences in Open Loop Fueling Tables.
- JDM has 5 Fueling tables defined. Following the order in ROM code and routines;
1st table is Primary Open Loop Fueling (KCA Alternate Mode)
2nd table is Primary Open Loop Fueling (Failsafe) (KCA Alternate Mode)
p.s.: KCA alternate mode seems to be enabled by default on this ECU. So those are the tables you will mess with to tune fueling.
3rd table is Primary Open Loop Fueling (KCA Additive B Low)
4th table is Primary Open Loop Fueling (KCA Additive B High)
5th table is Primary Open Loop Fueling (Failsafe)
- SADM has all 5 fueling tables, but only 2 defined.
1st table is Primary Open Loop Fueling - might be KCA Alternate Mode, but it's not described this way in the current definition
2nd table is Primary Open Loop Fueling (Failsafe) - might be KCA Alternate mode aswell, but not described too.
I think because KCA Alternate is also enabled by default, it was only defined those 2 tables as the other 3 didn't come into play and there was no point defining and editing the other 3?
Well, 3rd, 4th and 5th table exists, and even tho it's not defined, it is there, and my bet is that it works the same way as JDM.
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And there's more! In both ROMs, between 2nd and 3th table, there is another Fueling table that might be an offset or compensation to the active table, not a standalone fueling table.
In JDM, the table is fully populated with values.
Attachment:
myst-jdm-table.png
In SADM, the table is zeroed-out, so no offset or compensations.
Attachment:
myst-sadm-table.png