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Resolved Is this normal AFR reading / wideband behavior during cruise?

Vegas Smith

15+ Year Contributor
4,938
2,776
Dec 2, 2002
Houston, Texas
I never seen this anywhere. I’m at 1k rpm’s idle with isc at 30. Idle is butter.

I run the wb power (w inline fuse) and ground straight to battery. Gauge and link readings are identical.
Agreed. Stock ecu may target 750 but ecmlink can obviously target other rpms and the ecu will treat new rpms same as 750.
 

Kryndon

Proven Member
857
505
Jan 10, 2014
Bulgaria, Europe

BLACK wire - notes​

A good, solid high-current grounding point here. The ECU pins listed above are good choices or you can try a good, clean chassis ground point too.
NOTE: Do NOT connect the BLACK wire from the LC-2 to the ECU's sensor ground. You will damage the ECU's sensor ground track if you do this.

So. I was unaware that Ecmlink had an LC2 wiki page. As I assumed, you are unable to tie the ground to the Ecu sensor ground. Given that, I am unsure you will be able to 100% dial this in to perfect at cruise and not sacrifice accuracy elsewhere. They seem to suggest that you can use the LC1 preset and leave the black wire at chassis or ecu power ground. But there is a reason, when possible, they recommend using sensor ground.

Exactly. So how are the others running the same LC2 system on their cars and allegedly having both their gauge and ecm reading match? I thought maybe having the power source off the switched 12V wire from the headlights could be drawing too much current and skewing the reading, so then I just turned off the headlights and there was no difference whatsoever (disregarding the injector deadtime compensation due to the voltage change). I know for a fact my car is 99.9% boost and exhaust leak free and like I said, the readings match only during WOT. Also, both AFREst and LC2 Wideband have been configured to have a minimum and maximum values of 7:0 and 22:0 in their preference tabs. I made a quick video showing my LC2 gauge next to my laptop so you guys can see there is at least 1 point difference of reported AFRs. I remember Mr. Vegas suggested way back in my original thread of wiring the LC2 up, to simply run a relay and get power and ground right off the battery. I could try to do it like that but I have no guarantee it will change the logged value. Innovate themselves state that you can just use the headlight power wire and ground at the common ECU ground. I am lost...

Here's the video. Ignore the buzzing sound, my laptop was touching the dash and vibrating. Also what you are looking for is the gauge's reading and the lower PURPLE data item called "LC2WB". Could the actual controller need a hard reset even though I have not reprogrammed it in any way?

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Last edited:

llxkevinxll

Proven Member
444
203
Jan 29, 2012
Cleveland, Ohio
Exactly. So how are the others running the same LC2 system on their cars and allegedly having both their gauge and ecm reading match? I thought maybe having the power source off the switched 12V wire from the headlights could be drawing too much current and skewing the reading, so then I just turned off the headlights and there was no difference whatsoever (disregarding the injector deadtime compensation due to the voltage change). I know for a fact my car is 99.9% boost and exhaust leak free and like I said, the readings match only during WOT. Also, both AFREst and LC2 Wideband have been configured to have a minimum and maximum values of 7:0 and 22:0 in their preference tabs. I made a quick video showing my LC2 gauge next to my laptop so you guys can see there is at least 1 point difference of reported AFRs. I remember Mr. Vegas suggested way back in my original thread of wiring the LC2 up, to simply run a relay and get power and ground right off the battery. I could try to do it like that but I have no guarantee it will change the logged value. Innovate themselves state that you can just use the headlight power wire and ground at the common ECU ground. I am lost...

Factory reset using the programming tool might be worth a shot to ensure the 0-5V scaling is correct. I have had issues with the ECMLink logging of my MTX-L in the past that I resolved by doing a factory reset. The next thing to try is to adjust the ECMLink scaling of that input using Linear Wideband, instead of the LC1 preset. Start with typing it in exactly as it is set in the LC2, then modify as needed to get to matching at idle. Again, ECMLink is limited to basically just adjusting the slope of a linear line for these sensors, so if the disparity is more complex than simply a slope issue, it may be tough to get just right.

I attached a photo of how the scaling can be wrong, yet the AFR readings at gauge and ECU can be spot on during WOT and be off at idle. You can try playing with the Linear Wideband settings in ECMLink to get them to line up.

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llxkevinxll

Proven Member
444
203
Jan 29, 2012
Cleveland, Ohio
Just another thought here. Having checked your log finally, it seems like you are using a factory front O2. I see you mentioned that as well and I missed it. If that's the case, this might be a "don't care" situation. Annoying for sure, but getting the wideband to read correctly on ecmlink at idle and cruise won't give you any additional actionable information. The tuning will still be done using the fuel trims. You have a presumably functional narrowband O2 that is actually running the car in closed loop. And the wideband is recording correctly at WOT, the one condition you actually need it to work. So other than being a bit frustrating, this issue may not make much of a tuning difference for you.
 

Kryndon

Proven Member
857
505
Jan 10, 2014
Bulgaria, Europe
Just another thought here. Having checked your log finally, it seems like you are using a factory front O2. I see you mentioned that as well and I missed it. If that's the case, this might be a "don't care" situation. Annoying for sure, but getting the wideband to read correctly on ecmlink at idle and cruise won't give you any additional actionable information. The tuning will still be done using the fuel trims. You have a presumably functional narrowband O2 that is actually running the car in closed loop. And the wideband is recording correctly at WOT, the one condition you actually need it to work. So other than being a bit frustrating, this issue may not make much of a tuning difference for you.

Thank you for that feedback. I am aware of having stable close to 0 fuel trims however i thought my afrs should still hover around 14.7 for the programmed stoic burn? My idle is still fairly lean if im going by the gauge its 15.5-15.8 so thats why i want to be referencing accurate measurement equipment. If i see the gauge and link reading way too lean then i might suspect a leak or wrongly tuned fuel settings. Then again i am referencing my fuel trims. I will see if i can reset the controller and run it as a linear wideband.
 

1990TSIAWDTALON

Moderator
9,417
5,243
Nov 14, 2013
Independence, Kansas
Use LC-1 setting in Link for LC-2's
Red - 12v switched +
Black - ground to ECU ground NOT ECU SENSOR GROUND. Mine is at the ECU mounting tab (chassis ground)
Yellow - Pin 75 on a 2g, pin 4 on a 1g

White wire on DB gauge - tap into Yellow going to ECU so gauge reads what is on the ECU signal wire.

I have ALWAYS mounted mine in the front position with NO issues and simulated narrowband thru Link.
This is wired the same way on 2 of my 1g's and works perfect. My tuner had me ground my gauge and my controller both to the same CHASSIS ground (ECU mounting tab) as my ECU to get both to match up.
My .02 cents.
BTW, this thread is marked "Resolved" so if it was, a NEW THREAD should be started so others don't think this is their fix only to find that it wasn't "Resolved".
Marty
 

Kryndon

Proven Member
857
505
Jan 10, 2014
Bulgaria, Europe
Marty, I hope you'll allow me to fully close this thread as I have listened to all you guys and manage to really fix the issue this time!!

I relocated the LC-2 ground cable onto the driver side ECU bracket/bolt (main ECU ground remains under the radio bolted to the chassis).

I had to use the serial cable and LM Programmer to manually select the LC-2 controller to use the Bosch LSU 4.9 sensor and NOT the 4.2 like it was selected by default?? Had to re-calibrate once more.

Then I made the wideband log as a Linear Wideband, with the following values from Innovate's spec sheet:
Minvolts: 0,00v
MinLambda: 0,500 (7,34 AFR)
Maxvolts: 5,00v
MaxLambda: 1,500 (22.39 AFR)

Now my gauge and ecm are finally reading identical. My idle turned out to be perfectly set and hovering around stoich 14.7 (also Mr. Vegas you were right, no matter what you set the target idle RPM at, ISC can still remain at 30 so thanks for that!!). And under WOT I now see that I am almost a point richer (10.5 instead of 11.7) so I need to readjust my global and MAF sliders at high Hz.

Otherwise while cruising in closed loop and idling my AFR lines overlap nicely and my fuel trims are very close to zero.

CONCLUSIONS: AFR gauge will always read TRUE under all circumstances, so use that for reference. If you're using an Innovate LC-2 wideband you should set it up as Linear Wideband instead of using the available "LC-1" settings, as they seem to differ significantly at least in my experience. Also stubborn fellers like me should really listen to others and their experience
:coy::aha:


Thanks to everyone for their help.
 

1990TSIAWDTALON

Moderator
9,417
5,243
Nov 14, 2013
Independence, Kansas
We all try to come together here be as helpful as possible.
Super glad that it is all ligned out now!
I'll mark it RESOLVED if it doesn't already say that and thanks so much for the CONCLUSION to the issue. That is what a GOOD forum likes to see and I sure appreciate you taking the time to let us know that it was fixed!
Now HAPPY DSMing!!!:thumb:
Marty
 
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