Re: Leading guestions+1

["Bruce Plecan" <nacelp@bright.net>]

> Ya that would be the limiting factor :-)
> Scanning over c/l and o2 paramaters, it is possible to change the window
and
> the r/l setpoit volts.....in theory you caould have it cross over 1volt if
> ya wanted to...
> Can't find any value for the bias voltage..

There is at least on some ecms.
The 148 on the gns I think it was used a .5v where as the others used a
.440..

would be interesting to tinker
> with it on a bench and see if the bias voltage changed buy mod any of the
> paramaters....
>
> Correct me if I'm wrong.... But as long as the current stays the same..
you
> should be ok.

I thought the O2 input was a very high impedance?.  Meaning voltage
sensitive
Grumpy

> Mike Rolica
> Plant A,
> Magnesium Products Division
> Strathroy
>
> (519)-245-4040  Ext. 244
>
>
>
> -----Original Message-----
> From: Bruce Plecan [SMTP:nacelp@bright.net]
> Sent: Tuesday, August 15, 2000 8:24 AM
> To: gmecm@diy-efi.org
> Subject: Re: Leading guestions+1
>
>
> > Bruce Plecan wrote:
> > > If, I was to have a O2 sensor that worked at a different range
> of
> voltages
> > > then the gm use, could I just use a comparator at the new Os
> voltage
> level,
> > > and use it to switch from .1 to .9 volts, as it crossed it's
> 14.7:1?.
> > I don't think so.  GM likes to compute a long term average of the
> O2
> > voltage.  This average is used for some of the fine tuning during
> closed
> > loop.  The target average is specified in the PROM.  In one
> application,
> > this value changes between just about every PROM version.  A
> 4-speed
> > PROM has a different value from a 5-speed PROM, and both differ
> from an
> > automatic PROM, and so on.
> > You might be able to insert an analog amplifier (or voltage
> divider)
> > between the "new" O2 and the ECM's O2 input.
>
> Anyone happen to know what the max O2 voltage is before the ecm lets
> the
> smoke out?
> Or what the max O2 diacom will record.
> Grumpy
>
>
>


>