Cobb and Procede Stack - Bank 2 running extremely lean with flatlined fuel trims

[froop]

Hi,

I'm wondering if someone would be able to help me out with this issue. I recently had RB turbos installed and I had the mechanic change both pre-cat O2 sensors due to an issue I was having where my bank 2 AFRs are richer by about 1 point throughout the rev range and also at idle. Fuel trims for bank 2 are also higher indicating that although the AFRs are richer than the target it's also trying to add more fuel which doesn't seem to make sense. It's not a methanol thing since this happens at idle and also before meth sprays.

This is an example of the issue I was experiencing.

http://www.datazap.me/u/froop/201406...a=1-5-7-8-9-10


I recently changed to a Cobb and Procede stack and however today, I noticed that when datalogging I was running extremely lean in bank 2 and my fuel trims for bank 2 were flat lined and pegged at 0. This is the datalog.

http://www.datazap.me/u/froop/201407...a=1-5-7-8-9-10

If I turned off the engine and turned it back on again the AFRs would go back to "normal" (richer bank 2). On the way home though I kept getting this issue with normal driving and I had to pull over a few times to turn on/off the engine. I threw a CEL even with CANClear on and the following codes showed up when driving back home.

2C32 - Lambda probe in front of cataytic converter 2, trimming control
2C2C - Lambda probe in front of cataytic converter 2, system check
2C6C - Lambda probe behind catalytic converter 2, system check

Now the richer AFRs don't seem to be tune related since I've been having them with just the Procede, just the Cobb and with the Cobb and Procede stacked. I've had the front (pre-cat) O2 sensors replaced (as far as I know). Is it possible that a faulty rear (post-cat) O2 sensor is to blame?


Btw, here are a couple logs that I took today when the car wasn't running lean in bank 2. Car hauls ass . I've still yet to raise the boost and timing a little but I need to get this AFR/Fuel trim issue sorted.

http://www.datazap.me/u/froop/201407...7-8-9-10-11-12

Thanks,

Alex

[froop]

Bump!

I would love to know if anyone has had similar problems or if anyone has any suggestions. I've ordered 2 new rear O2 sensors, Bosch 16795 and 16796 and hopefully they won't take too longer to arrive from the states. They cost about $200 all up including shipping from the US. I looked up prices from Bosch in Australia and they were $260 and $320 each...

Also, I didn't specify in my original post, but every time I upload a new map on the Procede and/or the Cobb I have reset the adaptations via both.

[Tzu]

What exactly are you using the Cobb for? Fuel scaler? I see that the piggy still has quite a bit of bias added. Anyway, first step is to clear STFT and LTFT. I never had a fueling issue with Cobb.

[froop]

What exactly are you using the Cobb for? Fuel scaler? I see that the piggy still has quite a bit of bias added. Anyway, first step is to clear STFT and LTFT. I never had a fueling issue with Cobb.

I'm using the Cobb for fuel scalars for E50, AFRs and timing. The Procede is controlling OL fueling, boost and meth.

Everytime I change maps I use the ECU and adaptations reset on both the Cobb and the Procede. Does this not properly clear fuel trim adaptations?

What I don't understand though is that even if it were a fuel trim adaptation issue, it doesn't make sense that it would affect only one bank and also that the trims would be flat lined rather than pegged at + or - 34%.

[Tzu]

In your log, Fuel Cor parameter shoots negative, indicating that your AFR table in the procede is not zeroed. Check again that your AFR, timing, and OL fueling table are all zeroed. No need for the procede to do OL fueling, except for maybe a 10% reduction when spraying meth. Also, don't set OL fueling to 100%, people used to report funny things when they did. I always set it at 95% ish and modify the table directly. Not sure if the COBB resets LTFT. I know the procede only resets STFT. If you have access to INPA, then reset both LTFT and STFT and log again. Also ensure you are using the latest V5 maps for the procede, and a rev 2.5 minimum.

[froop]

In your log, Fuel Cor parameter shoots negative, indicating that your AFR table in the procede is not zeroed. Check again that your AFR, timing, and OL fueling table are all zeroed. No need for the procede to do OL fueling, except for maybe a 10% reduction when spraying meth. Also, don't set OL fueling to 100%, people used to report funny things when they did. I always set it at 95% ish and modify the table directly. Not sure if the COBB resets LTFT. I know the procede only resets STFT. If you have access to INPA, then reset both LTFT and STFT and log again. Also ensure you are using the latest V5 maps for the procede, and a rev 2.5 minimum.

Thanks Tzu! Would rep you if I could.

Yeah in those logs I had OL fueling set too high. I figured out I was adjusting it the wrong way when my fuel trims were negative already. My AFR table in the Procede is definitely zero'd out at 50 across the board but I'll double check. Timing on map 2 is zeroed out but I have map 1 with some mild timing retard (-2) towards redline in case I run out of meth.

I have an INPA cable but I don't know how to use it. I'll see if I can work it out, download the program and reset LTFTs.

[Tzu]

Np dude. Tag me if you need any more help.

[froop]

Np dude. Tag me if you need any more help.

Thanks Tzu. I checked my cobb logs from earlier in the week and LTFTs were both sitting at 0 so I'm still a little skeptical that it's adaptation related but I'll still give it a go with the INPA. Unfortunately I won't be able to do anything for the next 6 weeks since I snapped my upper arm in half on Sunday...

[Tzu]

Thanks Tzu. I checked my cobb logs from earlier in the week and LTFTs were both sitting at 0 so I'm still a little skeptical that it's adaptation related but I'll still give it a go with the INPA. Unfortunately I won't be able to do anything for the next 6 weeks since I snapped my upper arm in half on Sunday...

LTFT sitting at zero during a pull IS what makes me think it is adaptation related. Hope you heal up well dude.

[_ink]

I snapped my upper arm in half on Sunday.

WTF dude!??!!? I hope you're OK, that sounds crazy!!!

One thing you haven't ruled out is the procede, I'd uninstall to see if you are still getting those bank issues and run a cobb flash (without meth) to see if your trims/afr's are in check or if the procede has something to do about it.

[froop]

LTFT sitting at zero during a pull IS what makes me think it is adaptation related. Hope you heal up well dude.

ahhh ok, I've got much to learn! Thanks

WTF dude!??!!? I hope you're OK, that sounds crazy!!!

One thing you haven't ruled out is the procede, I'd uninstall to see if you are still getting those bank issues and run a cobb flash (without meth) to see if your trims/afr's are in check or if the procede has something to do about it.

Yeah haha... Only saw you just last week too lol

The AFR/Fuel thing also happens when the Procede is on it's pass through stock mode and was running the Cobb flash only.

My brother in law might help me with installing the O2 sensors when they arrive and also logging once it's (hopefully) fixed.

[RnmEvo9]

I used to have 2c2c and 2c32 periodically. I replaced the front o2 sensor with a new one and still threw the same codes. It wasn't until I reset adaptations that the car started to run strong again with no codes popping up.