Open Loop Confermation

[Bruce Plecan]

From: Joe Boucher <jboucher at ctelcom.net>
Subject: Re: Open Loop Confermation


>>Due to the untiring efforts of the west coast branch office of CSH, HQ,
>>it has been verified, that disabling the 44+45 code flags, and
disconnecting
>>the O2 sensor puts a 1227747 into open loop.
>>Cheers
>>Bruce     The staff at CSH, HQ were stunned into silence by this
>>               news.
>
>This is good because?:
>
>1) It is an interesting disection of the code;

sorta
>
>2) In open loop the amount of chip changes is simplified or;

sorta
>
>3) Some other reason I am to simple to understand.

Nope

What this means is you can lock out the "learning/corrections" of the
ecm, so that when tuning and doing initial calibrations the ecm, isn't
1 or more steps ahead of you.
  With the computer at open loop, you can try to have it run less than
14.7 (or whatever the target AFR, is), or greater than.
  If you in a country where leaded fuel is the norm, and it is legal you
don't have to run an O2 sensor.
  If you want to run a o2 sensor other than what gm usually does,
you can apply that correction in another manner.
  If your bench testing two ecms, you can taylor the injector pulse
widths to match, so one is a drop in replacement for the other.
>
>Joe (Wearing a double thick CSH)  Boucher
>'70 RS/SS Camaro  '81 TBI Suburban
>Joe Boucher
>'70 RS/SS Camaro  '81 TBI Suburban
>
Why are you wearing a winter hat??.

Cheers
Bruce