EFI: CO value (FI-diagnostic) vs. A/F ratio

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  • WRF-Rowdy

Posted June 26, 2015 - 04:46 AM


Today I played with the CO adjustemt tool, while having the O2 sensor connected.

Guys, make sure you are seated well: :p


CO   O2 Voltage

-21  0.91

-21  0.92

-22  0.90

-22  0.88

-23  0.79

-24  0.79

-24  0.61

-25  0.79

-25  0.71

-26  0.08  "lean" :thumbsup:


So my bike with my muffler/header and open airbox door (FI diagnostic tool)

develops lean idle only with a CO value below -25

That's right. Everything above -25 is on the rich side. 


So I dialed in -24 and through all my subequent freeway racing O2 sensor experiments (see other thread)

chopping the throttle closed got my some high 0.8, 0.9 reading,  CO -24 is A/F ratio wise rich idle !




CO-21 (2).jpg


CO-22 (2).jpg


co-24 (2).jpg


CO-25 (2).jpg



finally, at CO value set to -26 there is lean idle mixture:




Guys, please let's try and keep that thread focused on CO setting and idle mixture only.

A/F ratio and mapping is here:


Edited by WRF-Rowdy, June 26, 2015 - 05:54 AM.


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