BMW-Bob Posted June 15, 2023 Report Share Posted June 15, 2023 Hello everyone, quick question about CLL modes. My tune is really close with the CLL off, full range from part throttle cruise to full range rpm WOT. I am using a Bosch LSU ADV Wide Band sensor and controller. 14.7 idle to ~13.1 WOT (big cams - 4 cylinder) With CLL WB Stoich mode turned on, CLL works and I can see the idle AFR correcting and oscillating around 14.7. Adjusting the gain setting helps the response time, undershoot and overshoot. I can get this to work. With CLL WB Auto mode turned on, I'm watching the idle AFR in the ~15's and increasing, the CLL status shows reducing fuel. It cannot seems to correct the AFR to the target 14.7 It seems to be correcting in the wrong direction, and keeps leaning out the mixture. CLL WB Auto does not seem to work. I'd like to use CLL Auto to have full range correction. WB Stoich only seems to correct for part throttle, low load cruise to hold 14.7 I don't have a file handy to attach, I'm at work and cannot access it right now. suggestions? Quote Link to comment Share on other sites More sharing options...
koracing Posted June 15, 2023 Report Share Posted June 15, 2023 Make sure you're on the lastest firmware and software. You can set up 3D tables for maximum and minimum trim values if necessary if it's messing up at idle only, but that's not a good explanation as to why it would do that. I've also seen some cases where the noisy tps signal is actually adding acceleration fuel so a quick datalog should show if that is happening. Other than that yeah getting files attached on here for better help might be the best. Quote Link to comment Share on other sites More sharing options...
DerekAE86 Posted June 15, 2023 Report Share Posted June 15, 2023 I've seen something similar to this but I don't want to say what caused it without seeing your tune/log first because it might make you bark up the wrong tree. Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 15, 2023 Report Share Posted June 15, 2023 As others have said you need to attach some data, there are too many possibilities to even bother having a guess. 9 hours ago, BMW-Bob said: WB Stoich only seems to correct for part throttle, low load cruise to hold 14.7 Not really relevant to your problem, but just a FYI, WB stoich mode will target whatever AFR is in your target table and is not confined to low load or cruise, you can use it all the way to WOT if you wish. It is just a more basic strategy with a dither function so it can be used with a catalytic converter and is therefore slower to correct also. Quote Link to comment Share on other sites More sharing options...
BMW-Bob Posted June 19, 2023 Author Report Share Posted June 19, 2023 All, Thank you for the reply. I did get CLL Auto to work. I was pressed to time to get to the endurance race over the weekend. I had to populate and play with the Lambda Gain table {I think that's what it was called = having a rough monday morning after a race weekend} Engine ran great. Huge improvement in power and fuel consumption ! I did notice that I now have an ignition misfire in the 5300-5800 rpm range at full load / WOT. This didn't happen on the chassis dyno. Checking plug wires and plug heat range? Quote Link to comment Share on other sites More sharing options...
koracing Posted June 19, 2023 Report Share Posted June 19, 2023 If that's peak torque a weaker spark could be the issue as spark will struggle the most at the highest cylinder pressure - check plugs and ignition components and try a slightly tighter plug gap if all else check out. Could also post your tune with the dwell settings to see if someone with a similar setup has found a solution there. Quote Link to comment Share on other sites More sharing options...
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