C/L WB/WOT OEM ECUs...

[nacelp]

Subject: C/L WB/WOT OEM ECUs...


> >Q: any way
> >to move those useful and inexpensive OEM controllers into the realm of
> >WOT closed-loop ECU, once affordable AFR sensing becomes available?
> It's entirely TOO quiet around here! :)
>
> I can see how one might use an EGOR-module (or NTK box, or whatever) to
> set a "commanded AFR", and also how to simulate this AFR as the
> "stoich-crossing" to the ECU that's expecting to see a switch-type O2
> sensor input, that's the easy part; what I don't fathom completely at
> this point is how to KEEP the normal OEM controller, even at significant
> TPS/MAP/MAF inputs, from leaving C/L, ignoring our O2 input, and running
> outta it's open-loop fueling tables, as it normally would. I'm thinking
> that anyone who shows how this trick can be done is going to make a
> major contribution to opening up WB WOT to wide application and
> experimentation, not to mention bringing the cost way down from the
> FelPro's and Motec's.

I got several ideas, the basic question is to kludge or not to kludge.  For
the intial testing I see a Kluge as the easy way out.  That would be a
matter of just intercepting the TPS signal and tampering with it so that it
never reaches a high enough value for PE, to start. Yet at some point switch
from the oem sensor to the WB, or swich cross over points of the WB module.
   The tps interception could be as easy as just a voltage divide.  Just
picking numbers here, say PE starts at 4.0v, yet the max value is 4.3.  If
we use a 10:1 voltage divider the 4.3, drops to roughly 3.9 and that not
enough to hit PE, yet at idle if the min setting was say .65v, then that
would drop to .59, which should be a livable number for the ecm.  Then with
comparator set at say 3.5, we'd switch O2 sensors or cross over voltage for
the WB Module.
  Min Kludge devise is getting into the calibration file, and seting the PE
enable to 99%. and that should prevent the PE mode.  Then using a
comparator, off of the TPS, switch cross over points of the WB O2.
  I'll admit that these aren't the perfect answers as PID'ing in the
calibration would be best, but that get so specific as not to be practical
for all to enjoy.
Grumpy
>
> Anyone wanna light the fuse, and get what's likely to prove a
> barn-burner of a thread going? I cain't help; I'm pretty clueless when
> it comes to the OEM ECU end of things.
>
> Gar
>

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