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Discussion Starter · #1 ·
I'm curious on the function of the Lambda sensor.

The Lamba is closed loop only ..correct?

If the Lamba is unplugged....what ratio does the stock ECU revert to?

Why does EKG controller suggest to un plug the Lamba sensor? Wouldn't the stock ECU override the EKG controller and set a specific a/f ratio?

thanks in advance.

The reason I'm asking is because my FZ-07 now runs the Akrapovic with the CAT and the Baffle and it runs great but is slightly lean on the ECO throttle position and makes my hand go numb. I'm wondering what would happen if I unplugged the Lamba sensor.
 

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The 02 sensor is only used in closed loop ...with the stock ECM unplugging the 02 sensor will cause a very lean condition

aftermarket tuners will normally run the bike in open loop all the time, thus the 02 data is not used and the sensor can be unplugged or removed completely
 

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Discussion Starter · #3 ·
The 02 sensor is only used in closed loop ...with the stock ECM unplugging the 02 sensor will cause a very lean condition

aftermarket tuners will normally run the bike in open loop all the time, thus the 02 data is not used and the sensor can be unplugged or removed completely
Aftermarket tuners can't access the closed loop from what I heard.
 

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The O2 sensor will over ride any fuel controller in close loop. I tried few trick to go around it and leaving it plugged in was less worst.

With the EJK controller leaving it pkug in was the better compromise for good MPG. You can unplug it and it will run smoother but will kill the MPG.

What happen is the AFR spike from 15:1 to 13.5:1 without a fuel controller. It takes about 25 sec to trim down in safe mode at steady throttle. Adding fuel will take care of the 15s AFR but cruising will end up in the low 12s.
 

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What is the function of the O2 optimiser that comes with the PCV? Does that keep the AFR at a ratio that is chosen by Dynojet instead of taking the data from the ECU?

My lean surge during ECO/closed loop has totally disappeared since putting on the PCV with O2 optimiser. No missing or popping at idle either.
 

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Discussion Starter · #6 ·
What is the function of the O2 optimiser that comes with the PCV? Does that keep the AFR at a ratio that is chosen by Dynojet instead of taking the data from the ECU?

My lean surge during ECO/closed loop has totally disappeared since putting on the PCV with O2 optimiser. No missing or popping at idle either.
Are you running the "Auto Tune' with the PCV?
 

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Are you running the "Auto Tune' with the PCV?
No.

Just the PCV, and the O2 optimiser that came with. Using the M4 map available from Dynojet website. I also installed the Graves block off plates at the same time.

I was curious how the O2 optimiser works really, as I didnt think it would have as much affect as it did. My thoughts were that it interferes with the signal from the O2 sensor to the ECU or vice versa, and just keeps it at a steady AFR like the stock O2 sensor does........just at a not so lean setting. But I could be totally wrong, and would love to hear more info on how it actually works.

My bike used to have an awesome lean surge at cruising speeds, or anytime the ECO light was on really. And missed like a bitch at idle with any type of throttle input, a lot of times even without any input. Since the install, I have had not one hiccup, not one surge, not one pop or stutter. Idle is smooth as butter, and can slowly bring the revs up to near redline without any hesititation or inkling of a miss.

I was truthfully amazed at the difference.
 

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I'm curious on the function of the Lambda sensor.

The Lamba is closed loop only ..correct?

If the Lamba is unplugged....what ratio does the stock ECU revert to?

Why does EKG controller suggest to un plug the Lamba sensor? Wouldn't the stock ECU override the EKG controller and set a specific a/f ratio?

thanks in advance.

The reason I'm asking is because my FZ-07 now runs the Akrapovic with the CAT and the Baffle and it runs great but is slightly lean on the ECO throttle position and makes my hand go numb. I'm wondering what would happen if I unplugged the Lamba sensor.
Coincidentally was reading this today and found it a very helpful (to me anyway) overview of O2 sensor function.

BikeBoy.org - Fuel Injection – Open Loop and Closed Loop
 

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I was curious how the O2 optimiser works really, as I didnt think it would have as much affect as it did. My thoughts were that it interferes with the signal from the O2 sensor to the ECU or vice versa, and just keeps it at a steady AFR like the stock O2 sensor does........just at a not so lean setting.
that's exactly what it does.
 

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Discussion Starter · #10 ·
I was curious how the O2 optimiser works really, as I didnt think it would have as much affect as it did. My thoughts were that it interferes with the signal from the O2 sensor to the ECU or vice versa, and just keeps it at a steady AFR like the stock O2 sensor does........just at a not so lean setting. But I could be totally wrong, and would love to hear more info on how it actually works.
Reading that link the optimizer interferes with the signal from the 02 sensor like you thought. But according to that link...the stock 02 sensor does not create a steady AFR like you said. It is constantly changing plus or minus to add or subtract fuel. The target AF ratio for closed loop is set into the CPU {lean} and can't be changed unless something like the Optimizer on your bike alters it to a new {richer} target.
Hope that helps. The link finally explained to me what happens when the stock 02 sensor is disabled.
 
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Discussion Starter · #11 ·
What happen is the AFR spike from 15:1 to 13.5:1 without a fuel controller. It takes about 25 sec to trim down in safe mode at steady throttle. Adding fuel will take care of the 15s AFR but cruising will end up in the low 12s.
Correct...IF the 02 sensor is still plugged in. Unplugged..the CPU recognizes immediately a lean condition and corrects to a safe richer AF ratio.
 

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Correct...IF the 02 sensor is still plugged in. Unplugged..the CPU recognizes immediately a lean condition and corrects to a safe richer AF ratio.
Exactly. A narrowband O2 sensor creates a moving target (alternates continually between a high and low signal depending on AFR). When the O2 sensor is unplugged (and tuned around!), there won't be any regular compensation. If this is done properly, you'll have more consistent fueling during the closed loop region.
 

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One thing that I did notice too, which was counter intuitive to what I expected........my fuel mileage has actually increased. I have gained about an extra km per L. Not much at all I know, but in my experience with Power Commanders........fuel economy is not one of the resulting conditions after install.

Very surprising to say the least, and I have not been taking it easy since the install of the PCV and exhaust. Hard on it all the time, to hear those triple lungs singing via the M4.

So my performance mods are ECU flash, PCV, block off plates, M4 exhaust. More power, awesome sound, better fuel economy.......so it seems at this point anyway.

What more could a happy 09 owner ask for!!!
 

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Not to hyjack at all. Read the thread and I'm enjoying the info here. Question tho, what flash did you go with? Are block off plates necessary if the flash turns it off anyway?
 

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Not to hyjack at all. Read the thread and I'm enjoying the info here. Question tho, what flash did you go with? Are block off plates necessary if the flash turns it off anyway?
I am still unsure if my ECU flash turned it off. That was never mentioned, and I dont see it mentioned on the website I had my flash done by. ECUnleashed software, flashed by ECUWEST. No changes other than the standard flash, no fuel changes, my PCV will do that.

But for 30 bucks on the plates, I did it anyway. Takes off weight, and makes a cluttered area less so. You will be shocked at the weight of that tiny little pump.
 

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cool!
 
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