NB-O2 sensors suck! was Re: another wiring question

[jdbubb at ix.netcom.com (Dan Bubb)]

Let me rephrase:
It's only accurate at stoichiometric.
It's informative about whether your engine is running rich or lean.
It's useless at telling you how rich or lean. i.e. neither accurate nor
precise more than a couple tens of an A/F ratio away from stoichiometric.
The last line is just my opinion although it is a commonly held opinion
among those tuning aftermarket EFI. As an example, it would be a bad mistake
to attempt to tune a turbo engine using just a standard NB-O2 sensor!
Dan(the other Dan)

----- Original Message -----
From: "Drew Teague" <roccnroll@hotmail.com>
To: <jdbubb@ix.netcom.com>; <scirocco-l@scirocco.org>; <sad_rocc@yahoo.com>
Sent: Thursday, May 15, 2003 2:03 PM
Subject: Re: another wiring question


> >Also, you shouldn't expect too much as far as accuracy from this gauge.
It
> >will accurately tell you if you're at stoichiometric or whether you are
> >rich or lean, but it really will give you no idea HOW rich or lean. As an
> >example, if you were running open loop and at 15.5:1 while cruising down
> >the highway (which the engine would be totally happy with) the gauge
would
> >indicate dead lean. Very little accuracy on the lean side and not much
> >better on the rich side.
> >Dan (the other Dan)
> >
>
> So, in other words, it _is_ very accurate, just not *precise*  :)
>
>
> **Drew Teague**
> Harrisburg, PA
>
> '84 8v Rocco --  "Bruise"
> '85 BMW 318i
>
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