DIY-WB pc boards - (explanation)

[Ray Drouillard]

----- Original Message -----
From: "Wing Gee" <winggee at hotmail.com>


> i'm new here.
>
> after reading the page. so what exactly does this board do? from what i
> know. an O2 just sends out voltage. what does the board do with the
voltage?
>
> Thanks
> Wing

A standard O2 sensor tells you only one thing: Is the mixture too lean, or
too rich?  If stoichiometric is 14.7:1, having a mixture of 14.8:1 (slightly
lean) will give you almost the same output as a mixture of 25:1.  The same
thing happens on the rich end of the spectrum.

A UEGO or "wide band" sensor will actually give you a range of readings.
You can tell how rich, or how lean your engine is running.  Rather than a
simple "on/off" indicator, it is a true analog sensor.  The sensor itself
contains two elements, and requires special circuitry.  In theory, the
circuitry is very simple (a simple op-amp with the sensor in the feedback
loop), but becomes complicated by the various safeguards needed to keep from
frying the sensor.

The sensor is useful for tuning your engine because it allows you to tune it
somewhat rich at WOT (for maximum power), and somewhat lean when cruising
(for maximum mileage).  It is actually used in a lean-burn engine.


Ray Drouillard



----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org