AFR calc from Diacom data... was RE: Adding another O2 sensor

[Ludis Langens]

"Marteney, Steven J." wrote:
> 
> The 12.5:1 AFR goes back to pre-header days.  Coolant temps were running
> 190-195 back then.  Now, they have dropped to 175 with the headers and
> cooler, dryer air (something unusual for East Coast of FL).  I have never
> seen it drop out of CL mode, but am not sure.

If your CTS is really showing just 175, then you might very well be
stuck in warming-up enrichment mode.  FYI, the Fiero 2.8 stays in this
mode until CTS reaches 80C/176F.

Also note, the "closed loop" flag doesn't mean that the ECM, at that
moment, is using the O2 feedback for closed loop fuel control.  It
simply means that a certain subset of conditions has been met for CL. 
For example, ALDL will show CL even during PE (aka WOT) operation.

> My question, does the 8192 link show the commanded AFR?

I think so.  The mask $32 code (circa 1986) appears to send a two byte
value that's the commanded AFR.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/

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