Egil writes:
>Long time ago I promised some of you a status report regarding the
>usefullness of a lambda oxygen sensor.
[snip]
>For $30 and an hour work you suddenly get full control...
[snip]
>The display of three LEDs sold at various racing shops is pretty
>useless.
Unfortunately, the commonly available lambda (O2) sensors have a
very non-linear response curve, with a steep slope around 14.7:1
and virtually flat elsewhere. So the 3-LED gauges are really as
accurate as you can reasonably get. Modern engine computers use
the sensor as a binary input, e.g. 0=rich, 1=lean or vice-versa, and
adjust the mixture to continuously flip between the two values.
Wider range sensors (UHEGO's) are available, but cost roughly 15-20
times as much. Rumor is that some of the new lean-burn Honda engines
are using A/F ratios around 16:1 and are using the UHEGO's, so cost
may drop soon. Or you could spend $3,000 on a Horba exhaust gas
analyzer. For further info, find the DIY FI page (lost the bookmark).
Dave Williamson (silikal@aol.com) Spits in bits
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