[DefactoM6]

I've had my V4 (8-17, just loaded 27 firmware) installed for about a week and a half now, and I love it...

However, I have been seeing alarming lean spikes at WOT...16-17:1 AFR range. And I have yet to do a log where it hasn't shown up in some form. I emailed Shiv about these, and he said that they are normal, and that stock cars do this...however, take a close look at the pic...this really doesn't seem "normal" to me, and even if it is, that's not how I want my car to run.

Anyway, take a look at the pic. Notice that when I initially go WOT, AFRs are normal, then they go very lean, then they come back to more acceptable levels (I highlighted under the lean areas with red). Do you guys have the same thing going on? This doesn't seem normal or healthy to me, so I wanted to see what you guys thought. And if it is something that is occuring across the board, this is something that all tuners (not just Shiv) should shoot to tune this out of the stock maps. Thanks in advance...

[Ilma]

Which datalog variable are you using to log the A/F ratios?

[DefactoM6]

Sorry, the CAN cool temp graph (the bottom graph)=AFRs. I highlighted and circled the biggest recorded spike that occurred during WOT: 17.3:1 AFR!!! I also overlayed throttle input (the blue line on the bottom graph) to demonstrate that I am in fact WOT. That lean spike in the 3rd gear pull (the middle spike I highlighted) averages out to around 16.5:1 AFR. IMO, there is no reasonable explanation for this kind of behavior.

[Ilma]

Here's mine:

Same spike when going WOT, but my ratios settle at 10.5:1 which seems kind of rich...

Maybe I'm logging the wrong parameter......is it supposed to be Can coolant temp or Air/Fuel ratio?

[e93WhiteonRed]

Your A/F ratio blips are when there are changes in the throttle. If you let off the throttle it's normal to have your system go lean until you get back on it. Your A/F looks butter smooth while running up through the RPM's - I'd be happy to have it be that flat.

[Ilma]

Originally Posted by e93WhiteonRed

Your A/F ratio blips are when there are changes in the throttle. If you let off the throttle it's normal to have your system go lean until you get back on it. Your A/F looks butter smooth while running up through the RPM's - I'd be happy to have it be that flat.

Yes, the spike from lean to rich is very evident on the Procede in-dash air/fuel gauge (oil temp display) as you open up the throttle, the needle swings lean for a split second.

You can clearly see this on Shiv's video demo as well......so this appears to be normal.

But I still think I am logging the wrong channel.

Will try again later tonight and see if Can coolant temp is really the air fuel readings or not.......unless of course someone else knows and would be kind enought to chime in.

[ren]

Based on the channel unit descriptions "can knock" is the AFR for bank 1 and "can cool temp" is for bank 2. I have the same lean spike for a moment when I first step on gas as well, it logs around 17:1 and then goes to 12s at wot.

[Penn999]

I just got my car back from the dealership for throwing a lean code and I dont even have my tune in yet. My bmw tech said that this is fairly normal when you start adding bigger intakes and catless exhaust....which I have. He said it was no big deal, but if this happens to you on a regular basis I would ask shiv. I am getting the cp-e standback. Hopefully I wont have the same issues. What octane are you running? Not sure if it matters, just interested.

[DefactoM6]

I'm assuming you're referring to Ilma's graphs and not mine; if you look at mine, you will clearly see that my throttle inputs, as well as the actual CAN Throttle opening (I overlayed them both on the same graph) are fully WOT before, during, and after the spikes. You can even see that the car initially dives into a very healthy AFR right after going WOT, then it goes lean shortly thereafter. Furthermore, you can see that I overlayed the throttle log onto the CAN cool temp graph (it's the blue line), and that I am fully WOT. So my graphs clearly show a very real spike during full WOT situations.

Originally Posted by e93WhiteonRed

Your A/F ratio blips are when there are changes in the throttle. If you let off the throttle it's normal to have your system go lean until you get back on it. Your A/F looks butter smooth while running up through the RPM's - I'd be happy to have it be that flat.

Ilma, CAN knock and CAN cool temp are the AFRs from the left and right bank WBO2s (I forget which value corresponds with which bank). In my experience, they both get identical readings (but it would help for troubleshooting faulty injectors, etc), but you could log both and then average the two in the Math Channels part of the analysis program to determine what your average AFR is for all cylinders.

Originally Posted by Ilma

Yes, the spike from lean to rich is very evident on the Procede in-dash air/fuel gauge (oil temp display) as you open up the throttle, the needle swings lean for a split second.

You can clearly see this on Shiv's video demo as well......so this appears to be normal.

But I still think I am logging the wrong channel.

Will try again later tonight and see if Can coolant temp is really the air fuel readings or not.......unless of course someone else knows and would be kind enought to chime in.

Penn999, interesting that you went in for a lean code. I could possibly see a change in intake throwing off expected values for some sensors and making the car go lean until the computer can correct, but the absolute amount seems pretty huge, not to mention the fact that there is no perceivable fuel correction that occurs to create or eliminate the lean spike. The exhaust causing lean spikes seems like a bit of a stretch to me IMO. Good luck with the Standback, definitely post your findings, as there really is a need for more feedback on that system in this forum. You should be able to dial out lean spots in no time with it! As for talking to Shiv, I have (and I showed logs), and he said it's normal. IMO, just because it's the norm, doesn't mean that it's okay. There really is no good explanation for the lean spot.

Originally Posted by Penn999

I just got my car back from the dealership for throwing a lean code and I dont even have my tune in yet. My bmw tech said that this is fairly normal when you start adding bigger intakes and catless exhaust....which I have. He said it was no big deal, but if this happens to you on a regular basis I would ask shiv. I am getting the cp-e standback. Hopefully I wont have the same issues. What octane are you running? Not sure if it matters, just interested.

[Ilma]

Originally Posted by DefactoM6

Ilma, CAN knock and CAN cool temp are the AFRs from the left and right bank WBO2s (I forget which value corresponds with which bank). In my experience, they both get identical readings (but it would help for troubleshooting faulty injectors, etc), but you could log both and then average the two in the Math Channels part of the analysis program to determine what your average AFR is for all cylinders.

That's what I suspected.

I logged the wrong variable then.

Will relog later tonight and see what happens....but in any case, it looks like a bit of a spike is considered normal, but your's is far too long in duration.

[ren]

Originally Posted by DefactoM6

Ilma, CAN knock and CAN cool temp are the AFRs from the left and right bank WBO2s (I forget which value corresponds with which bank). In my experience, they both get identical readings (but it would help for troubleshooting faulty injectors, etc), but you could log both and then average the two in the Math Channels part of the analysis program to determine what your average AFR is for all cylinders.

Mine are never identical and if there is a spike it's only one of them, not both. But on average they follow the same trend.
I think Bank 1 is the driver's side.

[cn555ic]

Originally Posted by Ilma

That's what I suspected.

I logged the wrong variable then.

Will relog later tonight and see what happens....but in any case, it looks like a bit of a spike is considered normal, but your's is far too long in duration.

I have spikes but I agree OPs spikes duration seems to be longer than what I have logged...

[DefactoM6]

Alright, did some more runs/logging tonight...and...wait for it...I got a 18.9:1 SPIKE AT WOT! You read that correctly...18.9:1. At WOT. I don't care what anyone says, that is not good in any way, shape or form. Something needs to be done about this, pronto...I like the extra power of the Procede, but man, I don't like worrying about having a grenaded motor, and having BMW remotely interrogate my ECU and find out the real reason why. Shiv needs to release an update that corrects this, because this can't be good, no matter how "normal" anyone says it is.

[BrianMN]

Originally Posted by DefactoM6

Alright, did some more runs/logging tonight...and...wait for it...I got a 18.9:1 SPIKE AT WOT! You read that correctly...18.9:1. At WOT. I don't care what anyone says, that is not good in any way, shape or form. Something needs to be done about this, pronto...I like the extra power of the Procede, but man, I don't like worrying about having a grenaded motor, and having BMW remotely interrogate my ECU and find out the real reason why. Shiv needs to release an update that corrects this, because this can't be good, no matter how "normal" anyone says it is.

I thought /think the initial lean behavior is a result of the Lean Cruise feature. ..but these seem well into the pulls. I would like it to be possible to deactivate the lean cruise feature just incase

[OpenFlash]

I think I can provide some info here. Those lean spikes are caused by the voltage bias the procede applies to the wideband sensors. It is, in effect, telling the DME that the engine is operating leaner than it really is. Which makes the DME add the desired fuel enrichment. The period between this perceived condition and the DME response can take a second in some cars/software with certain DME software versions. You'll see this effect most obvious in the 3500-4500rpm range where we apply the biggest bias/fuel correction. If you put an actual wideband on the car, you wouldn't see the same lean spike at boost onset. Hope that helps clear things up.

[BrianMN]

Originally Posted by shiv@vishnu

I think I can provide some info here. Those lean spikes are caused by the voltage bias the procede applies to the wideband sensors. It is, in effect, telling the DME that the engine is operating leaner than it really is. Which makes the DME add the desired fuel enrichment. The period between this perceived condition and the DME response can take a second in some cars/software with certain DME software versions. You'll see this effect most obvious in the 3500-4500rpm range where we apply the biggest bias/fuel correction. If you put an actual wideband on the car, you wouldn't see the same lean spike at boost onset. Hope that helps clear things up.

Sounds good!

[vase330]

Shiv could you put it in layman terms? Are you saying the reading is not necessarily realistic and in effect don't worry?

[OpenFlash]

Originally Posted by vase330

Shiv could you put it in layman terms? Are you saying the reading is not necessarily realistic and in effect don't worry?

Yes. It's only going to have error in some cars that are slower to respond to AFR target error. Some DME versions behave this way. In the display logs, we assume no delay in DME response. And in most cases, this is fact. But this isn't always the case. The good news for those who are seeing measurement lag is that this is only measurement lag. You can confirm this by checking to see if both bank 1 and bank 2 give the same readings. On a similar note, this measurement delay is why leanrun watchdogs have timers/delays to prevent false triggering.

Shiv

[vase330]

Ah, thanks! Got it Shiv.

[Former_Boosted_IS]

Originally Posted by shiv@vishnu

I think I can provide some info here. Those lean spikes are caused by the voltage bias the procede applies to the wideband sensors. It is, in effect, telling the DME that the engine is operating leaner than it really is. Which makes the DME add the desired fuel enrichment. The period between this perceived condition and the DME response can take a second in some cars/software with certain DME software versions. You'll see this effect most obvious in the 3500-4500rpm range where we apply the biggest bias/fuel correction. If you put an actual wideband on the car, you wouldn't see the same lean spike at boost onset. Hope that helps clear things up.

I hope it is ok for me to ask a question, if not please just delete this post.

Shiv, I asked earlier if the wideband readings were accurate on the procede since there has to be an applied correction factor. At the time you said it showed the exact same as your innovative wideband. So I am correct that these wideband readings are definitely not as accurate as a standalone wideband? Why don't you just allow the 0-5v analog input from an aftermarket wideband, so you can integrate it into the tune? It seems this would be a slam dunk win.

[cn555ic]

Originally Posted by DefactoM6

Alright, did some more runs/logging tonight...and...wait for it...I got a 18.9:1 SPIKE AT WOT! You read that correctly...18.9:1. At WOT. I don't care what anyone says, that is not good in any way, shape or form. Something needs to be done about this, pronto...I like the extra power of the Procede, but man, I don't like worrying about having a grenaded motor, and having BMW remotely interrogate my ECU and find out the real reason why. Shiv needs to release an update that corrects this, because this can't be good, no matter how "normal" anyone says it is.

What software version are you running with your car..Program version??

[badass335]

+1

Originally Posted by Former_Boosted_IS

I hope it is ok for me to ask a question, if not please just delete this post.

Shiv, I asked earlier if the wideband readings were accurate on the procede since there has to be an applied correction factor. At the time you said it showed the exact same as your innovative wideband. So I am correct that these wideband readings are definitely not as accurate as a standalone wideband? Why don't you just allow the 0-5v analog input from an aftermarket wideband, so you can integrate it into the tune? It seems this would be a slam dunk win.