Heated NB o2 sensor just got booted.

[Dewayne_S]

For years I ran nothing but open loop and was very happy with how my car performed. A while back I decided to install a heated NBo2 to see if I could get a little better fuel economy. Once I started running closed loop I noticed the AFR's were bad lean, at time to the point where the engine was struggling to run. At idle the NBo2 would swing back and forth without changing the BLMs but as soon as you give it any gas the NB goes rich and starts cutting fuel.
Yesterday I disabled the learning to see what it would do in open loop. Fuel economy is up and the engine is not struggling to pull. AFR's on the WB are really tight around 14.7 but if you look at what the NB is showing the mixture is very rich. I think I got a bad part out of the box or something but I'm staying with open loop. Check out the screenshot I took.
Datalog stillshot.jpg

[ony]

did you try tunenning it in closed loop several times?

[Dewayne_S]

did you try tunenning it in closed loop several times?

Countless times have I attempted to tune it, nothing I did worked in closed loop so it will be open loop from now on. The engine runs great in open loop and like crap in closed loop. I wasted time and money trying to fix something that wasn't broken in the first place.

[EagleMark]

There's a lot of issues tuning with a Wide Band O2 sensor usually do to the WB not being accurate because of grounds. Then again it's a Lambda Sensor and converts Lambda to AFR for humans. They all come set to show the human 14.7 to 1 AFR when Lambda is Stoich is the first problem as all fuel at pumps has some ethonol in it and usually 10% which makes the AFR 14.13 AFR. It all comes down to the WB controller and how it is programmed. Then checking ground offsets!

At idle the NBo2 would swing back and forth without changing the BLMs

It's supposed to have cross counts! This keeps the AFR switching to keep the Cat happy. If you hit the gas and go into PE? Then it will stop the cross counts and be steady, this is the only time the NB data is even worth looking at. The NB sensor is very accurate at .451 voltage and not accurate anywhere else. But your reading of .981 is about right for WOT/PE afr of 12.5 afr or a Lambda of .85. Most engines will run better when a little richer then Stoich of the fuel they are using.

But something is wrong? You should be able to run CL... depending on your definition there are some O2 settings that can slightly lower or raise the Stoich point of .451 O2 Rich, Lean and Mean, by moving all three down say .100...

[Dewayne_S]

There's a lot of issues tuning with a Wide Band O2 sensor usually do to the WB not being accurate because of grounds. Then again it's a Lambda Sensor and converts Lambda to AFR for humans. They all come set to show the human 14.7 to 1 AFR when Lambda is Stoich is the first problem as all fuel at pumps has some ethonol in it and usually 10% which makes the AFR 14.13 AFR. It all comes down to the WB controller and how it is programmed. Then checking ground offsets!

It's supposed to have cross counts! This keeps the AFR switching to keep the Cat happy. If you hit the gas and go into PE? Then it will stop the cross counts and be steady, this is the only time the NB data is even worth looking at. The NB sensor is very accurate at .451 voltage and not accurate anywhere else. But your reading of .981 is about right for WOT/PE afr of 12.5 afr or a Lambda of .85. Most engines will run better when a little richer then Stoich of the fuel they are using.

But something is wrong? You should be able to run CL... depending on your definition there are some O2 settings that can slightly lower or raise the Stoich point of .451 O2 Rich, Lean and Mean, by moving all three down say .100...

The screenshot I posted was at a steady 60mph on flat ground when the nb was at 981. I agree something is wrong, as soon as I give it any throttle the NB goes to 9?? regardless to how much or how little throttle I give it.
I have moved the O2 settings from top to bottom and everywhere in the middle. At idle I have it offset the where it's not reading lean due to the overlap of the cam, didn't take but a couple tried to get that in a good spot. Off idle, I give up.
I also agree with the WB and the grounding issues and such. This WB is hooked up full time and is grounded with the ecm. I'm not saying it's perfect but it would be hard to find a better ground than how I have this car wired.

The car runs great in open loop and I'm not just watching the WB and seeing good AFR's when I say that. it even a little better on fuel economy. When I was struggling with closed loop that instant MPG number never hit 20 on flat ground, now it's 23/24 easily. I'm not sure how accurate that is but it is an improvement regaurdless. Besides, I can't keep my foot out of it long enough to save gas. LOL

[Six_Shooter]

Does you WBO2 have a NB sim output? You can try that for zero dollars and see if the same thing happens. If it does, it's in the correction, or more than likely a setting, such as the delay function of the NBO2 feedback. If this distance setting is too far off, you can get into a downward spiral where a correction takes place, but because the setting isn't correct, another correct takes place and so on, until the BLMs are at max and the engine is struggling to run.

[ony]

I don't know about wide band tunning, what ecm and engine set up you running?

[EagleMark]

You also could have changed something back when that never showed up till you went CL again? That's when I use the Compare option on TunerPro from the bin I'm using now compared to what I originally started from. It will show any difference, even a hex change that is not identified by a parameter!

[Dewayne_S]

I don't know about wide band tunning, what ecm and engine set up you running?

1227165 6E . 383 stroker with 280xfi comp cam, long tube headers and a Holley stealth ram intake

You also could have changed something back when that never showed up till you went CL again? That's when I use the Compare option on TunerPro from the bin I'm using now compared to what I originally started from. It will show any difference, even a hex change that is not identified by a parameter!

I use the compare option all the time, nothing really stand out concerning this but I have wondered if something I changed before I attempted cl was the problem.

Does you WBO2 have a NB sim output? You can try that for zero dollars and see if the same thing happens. If it does, it's in the correction, or more than likely a setting, such as the delay function of the NBO2 feedback. If this distance setting is too far off, you can get into a downward spiral where a correction takes place, but because the setting isn't correct, another correct takes place and so on, until the BLMs are at max and the engine is struggling to run.

ECM but didn't leave it since the sensor was mounted so far away from the engine. I have changed the Integrator Delay Vs. Airflow since I am running long tubes and the sensor is in the collector.

It's Tunerpro, I read the other day where some guy called it "simple software" so how hard can it be. LOL!!!!!!!

[ony]

I have never tuned a 165 ecm so I will stand aside, my 747 and 288 as they go closed loop its like adding 25-50 hp and the mileage goes up an seams like every thing smooths out as it gets to operating temp. ps I only got a 4.3 v6.

[EagleMark]

It's Tunerpro, I read the other day where some guy called it "simple software" so how hard can it be. LOL!!!!!!!

Well if WB output is into data stream it could be TP? Well not the software but the conversion for the WB Value.

Can you get the WB into $6E data stream? That would be the way to go. I alwasy use 2 values, one for the voltage as a sanity check and then one for Lambda... AFR if you must...

[Dewayne_S]

Well if WB output is into data stream it could be TP? Well not the software but the conversion for the WB Value.

Can you get the WB into $6E data stream? That would be the way to go. I alwasy use 2 values, one for the voltage as a sanity check and then one for Lambda... AFR if you must...

The WB has been in the datastream for years. The conversion is correct. Plus the way the engine behaves matches the wideband. The WB is not the issue, I even replaced it(controller and all) last year due to this just to be sure.