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Discussion Starter #1
I'll preface this by saying my wideband O2 sensor needs to be replaced most likely but I'm going to ask this anyway...

I have an Innovate Wideband. I assume it's programmed lambda is 14.7. My tune has its lambda set at 14.03. Will my wideband ever read properly now that my lambda for my tune is not the same as my wideband?

My tune is set to run at 11.5:1 (.82 lambda from the datalog from my tuner). My wideband never reads that rich...it's always a lot leaner (12.5-ish).

Again, I know my sensor needs to be replaced and I don't think the sensor likes to be as far into the exhaust pipe as it now (that is getting fixed also). Either way, will my 14.03 lambda mess with my wideband readings?
 

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You're confusing lambda and AFR in your first portion. Lambda is on a scale from 0 to 1.x. 1 is stoich lambda. Lower than one is rich. Greater than one is rich. Typical scales go from .6 to 1.2. (equivalent to 8.82 AFR to 17.64 AFR or so)
Here is some good info: Lambda VS. AFR: What's the Difference?
http://www.tatech.fi/cms/uploads/file/Lambda_vs_AFR.pdf

Are you running any extra ethanol in your tune? Likely, your tuner is setting stoich at 14.03 rather than 14.7 due to E10 blends, rather than straight unleaded gas. Stoich for straight unleaded gasoline is 14.7, stoich for E85 is 9.765. At E10 unleaded, your stoich would still be biased much closer to gas (14.7) but a little lower. I believe that is why your stoich AFR is set at 14.03.

Can you read Lambda, instead of AFR, from the gauge/sensor? I would like to see if Lambda is also reading wrong. The AFR reading on widebands comes from a voltage scaler equation and is converted from the lambda it is reading. If Lambda is correct it could be as easy as changing the equation on the gauge. If the lambda is reading incorrect than it could be the gauge, or your tune is not acting as it did on the dyno.

Remember, Lambda and AFR measure the same thing but in a different scale, where lambda is typically read from somewhere in the .6 to 1.2 range, vs AFR in the 8.82 to 17.64 range.
 

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Discussion Starter #4
You're confusing lambda and AFR in your first portion. Lambda is on a scale from 0 to 1.x. 1 is stoich lambda. Lower than one is rich. Greater than one is rich. Typical scales go from .6 to 1.2. (equivalent to 8.82 AFR to 17.64 AFR or so)
Here is some good info: Lambda VS. AFR: What's the Difference?
http://www.tatech.fi/cms/uploads/file/Lambda_vs_AFR.pdf

Are you running any extra ethanol in your tune? Likely, your tuner is setting stoich at 14.03 rather than 14.7 due to E10 blends, rather than straight unleaded gas. Stoich for straight unleaded gasoline is 14.7, stoich for E85 is 9.765. At E10 unleaded, your stoich would still be biased much closer to gas (14.7) but a little lower. I believe that is why your stoich AFR is set at 14.03.

Can you read Lambda, instead of AFR, from the gauge/sensor? I would like to see if Lambda is also reading wrong. The AFR reading on widebands comes from a voltage scaler equation and is converted from the lambda it is reading. If Lambda is correct it could be as easy as changing the equation on the gauge. If the lambda is reading incorrect than it could be the gauge, or your tune is not acting as it did on the dyno.

Remember, Lambda and AFR measure the same thing but in a different scale, where lambda is typically read from somewhere in the .6 to 1.2 range, vs AFR in the 8.82 to 17.64 range.
I’m wondering if I change my wideband to read lambda it will read lower lambda than the dyno log did but that still doesn’t explain why my AFR is wrong on WOT. I’ll change my wideband to read lambda and see what it reads.

If nothing seems to add up I’ll recalibrate the sensor, see if it changes. If not, I’ll put the ne sensor I just bought in and see what it reads.

Which model is it? Is it the MTX-L? If so, you can actually program the output function to be whatever you want.

https://www.innovatemotorsports.com/support/manual/MTX-L PLUS.pdf

Personally I just output in AFR and do the adjustments myself.
It is the MTX-L. Once I can get my hands on a serial to USB adapter I’ll switch it to read lambda. Go from there.

All of this trial and error is probably futile and I probably just need a new sensor (which I bought). No reason to have some fun and tinker around a bit.
 

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Discussion Starter #5
I programmed the gauge to be 14.03 as 1 lambda.
I changed the output to lambda.
I recalibrated the sensor.

I’ll let you know what I see in the next few days.
 

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o2 blues

If you are sure about your air fuel is at 14.1 and thats with gasoline your safe as somone mentioned E-85 and methonal blends this changes the adequate ratio. I love E-85 but you need to be capable 30% more fuel this means a gas ratio is not adequate any longer. You may find a shop with a hydrocarbon sniffer this may help.
\
Ditymike
 

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I programmed the gauge to be 14.03 as 1 lambda.
I changed the output to lambda.
I recalibrated the sensor.

I’ll let you know what I see in the next few days.

Any updates? Sometimes the sensors do go bad, and in some cases the idiot driver puts it in at the wrong orientation and slams the sensor against a driveway breaking it in half...(I don't know who could have done that...hint: it was me).

If you are sure about your air fuel is at 14.1 and thats with gasoline your safe as somone mentioned E-85 and methonal blends this changes the adequate ratio. I love E-85 but you need to be capable 30% more fuel this means a gas ratio is not adequate any longer. You may find a shop with a hydrocarbon sniffer this may help.
\
Ditymike
I did mentioned E85 or Ethanol in general since OP stated his tune had lambda set at 14.03 (he meant AFR as far as I can tell). That is either slightly rich for his stoich target, which could have been done for safeties sake (14.7:1 being gasoline stoich) OR the tuner set him up based on E10 XX Octane fuel, since that is the standard these days.

Back to OP, hopefully the change of transfer function makes it work as it should, and if not it would likely still have been needed even with the new sensor. Since the default transfer functions are based on 14.7 stoich and you are set up slightly different from that.

Again, hopefully it all works out!
 

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Discussion Starter #8
Any updates? Sometimes the sensors do go bad, and in some cases the idiot driver puts it in at the wrong orientation and slams the sensor against a driveway breaking it in half...(I don't know who could have done that...hint: it was me).



I did mentioned E85 or Ethanol in general since OP stated his tune had lambda set at 14.03 (he meant AFR as far as I can tell). That is either slightly rich for his stoich target, which could have been done for safeties sake (14.7:1 being gasoline stoich) OR the tuner set him up based on E10 XX Octane fuel, since that is the standard these days.

Back to OP, hopefully the change of transfer function makes it work as it should, and if not it would likely still have been needed even with the new sensor. Since the default transfer functions are based on 14.7 stoich and you are set up slightly different from that.

Again, hopefully it all works out!
UPDATE: It is still reading lean. Anywhere from .86-.89 at WOT. That is dangersouly lean so if it actually is running this lean I would think I would have melted a piston by now. Maybe not....

Next steps will be a new sensor. That will take a bit since I bought a new midpipe and will have the new bung I ordered welded to that pipe l.

Stay tuned...
 

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since everyone else from Columbus is weighing in on this....

Did the engine sound different or run different?
It does sound like a bad sensor assuming nothing has changed since dyno day and you are using the same fuel blend, that, and you said you think it's bad anyway.

Oh, and don't forget exhaust leaks, nothing makes a false lean reading like some fresh air getting pulled into the pipe. if You are like me, I had issues with all the stupid mid pipes sealing near the passenger side, turns out K member was shifted and caused clearance issue ect.
 

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since everyone else from Columbus is weighing in on this....

Did the engine sound different or run different?
It does sound like a bad sensor assuming nothing has changed since dyno day and you are using the same fuel blend, that, and you said you think it's bad anyway.

Oh, and don't forget exhaust leaks, nothing makes a false lean reading like some fresh air getting pulled into the pipe. if You are like me, I had issues with all the stupid mid pipes sealing near the passenger side, turns out K member was shifted and caused clearance issue ect.
Theres more of us... we should have a meet up or something...

@ OP, One other option for short term diagnostic, though not the best long term solution. if you are catless, you can put the new sensor in one of the rear O2 bung locations and see how it reads. The reading wont be as accurate, due to the difference in location, but it should be pretty close. That may hold you over/further solidify if it is the sensor, before you can swap the midpipes. You may be a code if you have the rear O2 unplugged though, but if you are catless you likely have a mil elminiator in place on the stock wiring or they are turned off in the tune.

if you are catted the reading will be much more inaccurate due to the change in gasses after going through the cat...
 

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Discussion Starter #11
since everyone else from Columbus is weighing in on this....

Did the engine sound different or run different?
It does sound like a bad sensor assuming nothing has changed since dyno day and you are using the same fuel blend, that, and you said you think it's bad anyway.

Oh, and don't forget exhaust leaks, nothing makes a false lean reading like some fresh air getting pulled into the pipe. if You are like me, I had issues with all the stupid mid pipes sealing near the passenger side, turns out K member was shifted and caused clearance issue ect.
No echaust leaks, I did check for that. Nothing has changed. Car sounds and behaves just like it did on dyno day. Doesn't misfire, hiccup, nothing...just pulls hard like it should.

Theres more of us... we should have a meet up or something...

@ OP, One other option for short term diagnostic, though not the best long term solution. if you are catless, you can put the new sensor in one of the rear O2 bung locations and see how it reads. The reading wont be as accurate, due to the difference in location, but it should be pretty close. That may hold you over/further solidify if it is the sensor, before you can swap the midpipes. You may be a code if you have the rear O2 unplugged though, but if you are catless you likely have a mil elminiator in place on the stock wiring or they are turned off in the tune.

if you are catted the reading will be much more inaccurate due to the change in gasses after going through the cat...
The sensor has been and is currently in the driver side rear O2 bung (since my current mid pipe does not have the extra bung on it). I have long tubes and where it's located is actually a good distance from the collector based on what Innovate recommends. The only problem I see with how it is now is the sensor itself stick into the exhaust path about 3/4 of inch and innovate recommends just the tip of the sensor to be at the edge of the pipe (sing the extended bung they provide). That is most likely killing my sensor...it's pretty freaking black...

I'm definitely leaning towards a bad sensor but it does read fine other than at WOT.
 

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The only problem I see with how it is now is the sensor itself stick into the exhaust path about 3/4 of inch and innovate recommends just the tip of the sensor to be at the edge of the pipe (sing the extended bung they provide). That is most likely killing my sensor...it's pretty freaking black...

I'm definitely leaning towards a bad sensor but it does read fine other than at WOT.
It should stick into the exhaust flow significantly. This is based on the documentation I have from sensor suppliers, particularly Bosch and NTK. You want the base of the tip more or less flush with the inner diameter of the pipe.

I would check your STFTs and see what they say. If they, or the bank they're on, match your sensor, you've got another problem. If that bank is totally different than the sensor, then I'd replace the sensor.
 

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Discussion Starter #13
It should stick into the exhaust flow significantly. This is based on the documentation I have from sensor suppliers, particularly Bosch and NTK. You want the base of the tip more or less flush with the inner diameter of the pipe.

I would check your STFTs and see what they say. If they, or the bank they're on, match your sensor, you've got another problem. If that bank is totally different than the sensor, then I'd replace the sensor.
Interesting. Innovates isntructions say otherwise but that's not to say they are the authority. I'll check my STFT next time I'm out with the car.

Good to know, thanks for the information. Can I compare STFTs from a narrowband to the lambda reading from the wideband? Again, both are set to 14.03 = 1 lambda.

---------- Post added at 02:31 PM ---------- Previous post was at 02:22 PM ----------

If it matters it's a Bosch LSU 4.9
 

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Yeah Innovate isn't the sensor manufacturer so I wouldn't put that much weight on it.

STFTs represent a percentage compensation/deviation from target lambda, and are capped at +/- 25% (0.75-1.25). If you really are going lean, I would expect to see your STFT pegging at 0.75 trying to enrich it.

Just keep in mind it isn't an instantaneous update so as long as it trends to 1.00 +/- 0.05, that means you're more or less under control.
 

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Yeah Innovate isn't the sensor manufacturer so I wouldn't put that much weight on it.

STFTs represent a percentage compensation/deviation from target lambda, and are capped at +/- 25% (0.75-1.25). If you really are going lean, I would expect to see your STFT pegging at 0.75 trying to enrich it.

Just keep in mind it isn't an instantaneous update so as long as it trends to 1.00 +/- 0.05, that means you're more or less under control.
I logged STFTs today and it goes to .82 and stays there, which, again if you multiply that out it is 11.5 AFR but this is a from a narrowband. My wideband was reading the same as it normally does anywhere from .86-.9 (which is super lean and I don't think the pistons would survive being that lean...). I'm welding my bung on the new midpipe tomorrow night and will put the new sensor in and let you all know what the results are.

If it helps, ECT were in the high 170s, and IATs were under 100 degrees (closer to 80 degrees). Total Timing is always around 14-15 degrees ...it was a cool morning today.

Thanks for all the input.
 

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I logged STFTs today and it goes to .82 and stays there, which, again if you multiply that out it is 11.5 AFR but this is a from a narrowband. My wideband was reading the same as it normally does anywhere from .86-.9 (which is super lean and I don't think the pistons would survive being that lean...). I'm welding my bung on the new midpipe tomorrow night and will put the new sensor in and let you all know what the results are.

If it helps, ECT were in the high 170s, and IATs were under 100 degrees (closer to 80 degrees). Total Timing is always around 14-15 degrees ...it was a cool morning today.

Thanks for all the input.
STFT is the short term fuel trims. It going to .82 means that short term the long term trim is lean, and the car is richening up. As Wicked said, .75 is the rich limit on the car for STFT, so it can not enrich (add fuel) past that. Your lean vs. rich understanding of AFR is also backwards, AFR larger than 14.7 (standard stoich) or in your case 14.03, is considered LEAN afr. AFR less than that, is rich. 11.5 for instance is pig rich, much richer than needed. BUT STFT is not a lambda value so you cant compare it directly, it is a trim, that the ECU uses to add or subtract fuel, STFT lower than 1 means that the ECU is adding fuel to hit the fuel target, STFT larger than 1 means that the ECU is pulling fuel to keep the target.

What this means, and what I should have noticed before but was skimming, is that your either running rich, OR your sensor is reading rich. You said your lambda was .86 to .89, that is rich AFR. Rich is better than lean to some degree, but can still cause cylinder washing, etc. but wont melt a piston the same way.

TLDR; your STFT supports that fuel is being added to hit your target lambda. Do you have the ability to log anything named Lambda or Lambese from the SCT tuner? IDK if its on cars that are factory narrowband, but it would be nice to see the targets set in your tune if you can see them, as well as what the car is seeing and doing on the narrowband sensor.

Another thing to check, you could try and change the narrowbands, and see if your STFT goes closer to 1, if they are throwing off the reading, and causing it to richen up, that could explain some of what you see. Do you recall which STFT you looked at (there should be bank 1 and bank 2, one of which is driver side and one passenger side). Are both the same?
 

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Discussion Starter #17
Both STFTs are were reading .82 on the tuner (narrowband). The wideband reads .86-.9 (which would be 14.03 * those values...which is LEAN at WOT for a boosted car...it should be reading around .82 to hit the target 11.5:1 AFR..or around there). According to the wideband I'm running pretty lean at WOT for a boosted car (anywhere from 12.06:1 to 12.6:1 AFR). I may not be communicating it properly...

The tune is again set at 1 lambda = 14.03AFR; my wideband is also set to 1 lambda = 14.03 AFR.

My LTFTs are always 1 and those never change when I datalog...not sure what that means...

I just know the log from my dyno tune (which I saw) read .82 from the wideband my tuner used, all the way to redline which is 11.5:1 AFR. (.82*14.03).

I still think my wideband is reading wrong...just trying to learn what all I'm reading and seeing in the logs and on the wideband itself.

Is this making sense? I'm sure I'm not communicating it the best...
 

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Both STFTs are were reading .82 on the tuner (narrowband). The wideband reads .86-.9 (which would be 14.03 * those values...which is LEAN at WOT for a boosted car...it should be reading around .82 to hit the target 11.5:1 AFR..or around there). According to the wideband I'm running pretty lean at WOT for a boosted car (anywhere from 12.06:1 to 12.6:1 AFR). I may not be communicating it properly...

The tune is again set at 1 lambda = 14.03AFR; my wideband is also set to 1 lambda = 14.03 AFR.

My LTFTs are always 1 and those never change when I datalog...not sure what that means...

I just know the log from my dyno tune (which I saw) read .82 from the wideband my tuner used, all the way to redline which is 11.5:1 AFR. (.82*14.03).

I still think my wideband is reading wrong...just trying to learn what all I'm reading and seeing in the logs and on the wideband itself.

Is this making sense? I'm sure I'm not communicating it the best...
Lambda is AFR/AFR stoich, so for you with stoich being set at 14.03. I probably confused my self because I was looking at it from 14.03 being the set point and less than that as rich, greater as lean, but if your targeted WOT AFR is 11.5:1, then you are running leaner than that based on what you're seeing.

Due to that the STFT is compensating, by adding fuel to richen the mixture. And it is adding a decent bit based on what you're seeing. If STFT is adding fuel at a constant rate, than it should be moving the LTFT as well...not sure why it isnt in your case.
 
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