What is the difference between
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FormerVendor
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What is the difference between
Power Enrichment and Open loop Fuel air
I know when I am WOT I am in open loop so if i wanted to lean out my mixture for 100 kpa and rpms greater than 5K which table would i use
Pe vs Rpm or Open Loop F/a
TIA
I know when I am WOT I am in open loop so if i wanted to lean out my mixture for 100 kpa and rpms greater than 5K which table would i use
Pe vs Rpm or Open Loop F/a
TIA
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I have been told that the way it works, is the PCM
picks the richest alternative. You have PE vs RPM,
and you have open loop AFR vs MAP & ECT. If PE
gives you fatter, you get the PE number. If Open
Loop is fatter, you get that. The PE only applies
above the MAP threshold and runs w/ RPM while
Open Loop is MAP-parametric. So you really have
two degrees of freedom (including freedom to
screw up) here. I think to do it right you'd want
to use both, but need something like an Excel
second-order map of it to make sense - like get
both tables in there, and then surface-plot the
max(PE(RPM),OL(MAP)) function to see what
you will get.
Why PE is not a function of MAP and RPM, I
have wondered for a while. I guess at WOT
you would assume MAP=100kPa. But PE applies
down pretty low, like MAP>=15kPa in some
tunes. Open loop I believe is any time the
fuel/air multiplier <>1.00.
Anyway, to lean you out you would look at
which of them is in control. If you knocked
PE way down but OL was still a bit chubby,
you might not get as much effect as expected
from the PE change.
picks the richest alternative. You have PE vs RPM,
and you have open loop AFR vs MAP & ECT. If PE
gives you fatter, you get the PE number. If Open
Loop is fatter, you get that. The PE only applies
above the MAP threshold and runs w/ RPM while
Open Loop is MAP-parametric. So you really have
two degrees of freedom (including freedom to
screw up) here. I think to do it right you'd want
to use both, but need something like an Excel
second-order map of it to make sense - like get
both tables in there, and then surface-plot the
max(PE(RPM),OL(MAP)) function to see what
you will get.
Why PE is not a function of MAP and RPM, I
have wondered for a while. I guess at WOT
you would assume MAP=100kPa. But PE applies
down pretty low, like MAP>=15kPa in some
tunes. Open loop I believe is any time the
fuel/air multiplier <>1.00.
Anyway, to lean you out you would look at
which of them is in control. If you knocked
PE way down but OL was still a bit chubby,
you might not get as much effect as expected
from the PE change.