Misc ?? EFI

[Jason Weir]

Bill the arcstarter wrote:

> It was written:
> >>     While in PE it stays closed loop but it no longer is in learn
> mode,
> >> meaning that the BLM and INT values are no longer being modified,
> the
> >> same thing happens on closed throttle deceleration, it stays in
> closed
> >> loop but learn mode turns off.
> >
> >On Fri, 20 Nov 1998, Scot Sealander wrote:
> >
> >> When in PE, the process is open loop, i.e., the feedback device is
> not
> >> being used.
> >
> >I've seen both these conflicting viewpoints expressed before.  To me,
>
> >"closed loop" refers to a control process that is presently using
> feedback
> >(like an O2 sensor) to maintain some parameter (like AFR).
> >
> >It may be just a question of semantics, but I think it is hindering
> some
> >of the discussions.  If we can't all be on the same page, knowing
> what
> >individuals mean by their use of "closed loop" may be good enough.
>
> So it sounds like there are two different processes to consider:
> 1) The processing of the self-learn, ie, adjustment of BLM, INT values
>
> 2) The injector fuel delivery is trimmed based on O2 and other sensor
> inputs.
>
> I would nominate the term "Closed-loop" to mean item #2.  Any
> comments?

Bill,
 I think the 7747 ECM would agree because at start both closed loop and
learn mode are off, they both come on at the same time but after that
learn control can come on and off but closed loop status stays on, but
of course if the thing goes open loop then learn mode will be off as
well... so in short #2 I agree also

--
Jason Weir
88 Wrangler - 258 Chevy TBI
Fayetteville, North Carolina
http://home.att.net/~jweir  --- Jeep Home Page
mailto:jweir at att.net