Oxygen sensor

[Bruce Plecan]

-----Original Message-----
From: Barry Tisdale <btisdale at cybersol.com>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Saturday, December 26, 1998 10:54 PM
Subject: Oxygen sensor


>Put together the oxy sensor bargraph display discribed elsewhere here, and
am puzzled @ the display.
>
>At moderate & heavy accelleration, indicates about 800-900mv, holding
steady; @ cruise, or any part-throttle condition, bops back & forth from
<100mv to about 600, nice & regular.  This checks w/ scantool reports.

The ecm toggles the air/fuel rato rich to lean to maintain a 14.7:1
Average.  Steady high voltage under acclerration means richer than
14.7, which is fine.

The injector on time is modifed by the feedback information, supplied
by the O2 sensor.   So any modification that you make, that the ecm
can see, will affect the cars runnning.
Bruce
>
>Question: is the O2 sensor involved in moment-to-moment injector decisions,
or just to activate a trouble code should things get seriously awry?

Yes, to both
>
>Would a capacitor/resistor combo to integrate the input to the 3914 yeild
any meaningful info @ cruise?  Cute display, but for what?  Or is something
broke on my vehicle??
>
>Thanks - Barry
>