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How to hook up analog output of any Air fuel meter to the Yuminashi stand-alo...

6936 Views 11 Replies 7 Participants Last post by  hobbycaptain
Today i decided to experiment with my analog output to see if I could get it to work with the stand alone ECU. To my surprise it works great. This is great news and is really easy to hook up.

First take your analog output wire from your AF meter (most have one), in my case the yellow wire coming from the back of my NGK AFX and plug it directly into the plug for the o2 sensor. I just used the female end of a bullet connector which works great.

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Next go into the yuminashi software under the setup tab and then click on "oxygen sensor characteristics setup".

Once this screen pops up enter the values provided by the manufacturer of your Wide band AF meter to define the parameters. Make sure you go from 5v to 0v from left to right, which seems backwards, but is how it needs to be done. Afterward enter the corresponding AF ratios to those voltages.
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I used this chart for mine:

Once you are done press "enter" on your keyboard to send the data to the ECU. Now the meter will not only read your current AF ratio, it will log the data in the AFR monitor tab by automatically putting the values into the table making tuning way easier.

Here is an example with the engine running, the engine is cold here and i still need to adjust the enrichment values under the enrichment corrections tab so it runs leaner when the engine is cold, but this gives you an idea of what it can do.

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I am loving this ECU and and its capabilities. Ill make a video on how to use the software soon and get it posted.

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that is great news to know.

I do like the stand alone ECU that comes with the Yuminashi kit, I'm looking at all the parts that you get with the kit and was wondering it would be great to try most of the parts with BrianS 170cc kit, meaning using the ECU, extended valves with the duel spring setup, cam, clutch springs, and stock heads. I assume it will pull like a freight train compared to a stock Grom.

too bad some software engineer can't come up with a solution to use a smart phone or smart device that can connect to the ECU or even the PCV via blue tooth so you can do your adjustment that way.
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