Psi363 wrote:
>
> In a message dated 98-04-30 10:17:00 EDT, you write:
>
> << Unless something electrically or physically damaged the computer in some
> way (they really design these things to be pretty rugged as the
> underhood environment is pretty hostile to lil' old electronics parts),
> once you restore the original sensor inputs the computer will resume its
> previous control patterns. Not sure what year your Dak is, but the 97-98
> computers are supposed to adapt very quickly - a few hours to a day. The
> older models do take longer.
> >>
> Can you tell me exactly what the computer is "learning"? It seems that
> driving habits could end up effecting performance, if so, in what way?
>
> Wayne
Sorry Wayne, I'm not sure exactly what parameters are "learned". Maybe
some of the other folks on the list know more of the intricate details
about the Dodge SBEC or others.
However, I'm willing to insert foot in mouth and take a stab...
The SBEC must adapt to changing engine performance as components wear
and environmental conditions change (ambient temp for example). Since
alot of the sensor inputs are dynamic (change alot) and may have a wide
range of acceptable values, the SBEC probably averages some of these
values out to watch performance trends and to keep control responses
smooth. To average any parameter requires that that the SBEC store some
history (previous values) for that parameter.
It would seem that air flow rate at a given rpm is a learned value. The
computer must monitor the airflow performance through the air filter, so
that it can adjust fuel metering appropriately as the filter flow
decreases with age (accumulated dirt restriction). This is why the
computer can adapt and improve performance after an open element air
filter is installed.
Of course I may be totally off base here. I'm no expert on engine
control computers, though I have spent some years doing controller
design for a number of other applications. Somebody with more knowledge
on this topic is welcome to jump in and educate us all...
jeff
98 rc 4x2 v8 5spd 3.55sg flares fipk
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