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voda1
September 11th, 2017, 01:45 PM
When configuring LS1A for OL/MAF what determines what is controlling commanded fuel, B3605 or B5001?
B0120=0
B3801=disabled
B4205=140c

Highlander
September 11th, 2017, 02:38 PM
B3605 and B3618 (the richer of both)

B5001 is MAF Curve will control actual fueling and not commanded AFR.

joecar
September 11th, 2017, 02:41 PM
MAF B5001 and VE B0101 are tables which feed into the cylinder airmass calculation;

OLFA B3605 and PE B3618 are commanded fuel tables, these are applied on top of cylinder airmass;

at any instant, regardless of MAF/VE, the commanded fueling comes from the richest of the active fuel tables at that instant (i.e. on a cell-by-cell basis)...

in OL, B3605 is active;
in PE, B3618 is active (regardless of OL);


if PE is not active, then B3605 will be the active table;
if PE is active, then the richer of B3605 and B3618 will be the commanded fuel;
if engine/piston protection modes are active, then the richer of B3605, B3618, B3603, B3659 will be active;
if COTP is active, then while we can't see its table, we know COTP commands EQR 1.25, this will be commanded fueling if it is richer than the currently active tables.


So B5001 determines the cylinder airmass (log GM.CYLAIR_DMA), and B3605 determines commanded fueling (if PE is not active).


The other trick GM built into their code is this:
if the richest of the active tables is leaner than stoich, then stoich will be commanded.