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I'd like to have a go at getting O2 closed loop feedback working with datalogit so I can get some stable fuel ratios off boost. I don't have a fuel temperature sensor so on long journeys, it seems like I am getting some small fluctuations when temperatures change. That, I think, is the only explanation I have for my fuelling going slightly lean (0.5 AFR), on a long journey (150+ miles). I've checked air temperature, voltages, fuel pressure and all the corrections available to me to no avail. I've also raised before that I get a lean condition when turning air conditioning on which is annoying again; grounding all seems fine and voltage corrections seem fine. I've been investigating and found that from most tuners, you'll get these problems if you're running everything in open loop because there's just so many things that need correcting, i.e. a small rise in fuel temp changes the amount delivered. I've got a regularly calibrated MTX-L wideband that I use for tuning which is plumbed into AN1-AN2 on datalogit. I've got O2 feedback turned off because I don't have any narrowband sensors on my car but I was thinking that I would be able to turn the MTX-L to provide output in lambda instead of AFR. If I do this, where do I sort the wiring? is it basically wiring the wideband into the loom that goes into PowerFC? Datalogit just shows 0.005 for O2-1 and O2-2 constantly. I would assume that once PFC sees the wideband putting out the voltages it expects for the O2 sensors, it shouldn't care whether it's a wideband or a narrowband and my AFR problems will go away. I can have the MTX-L display gadget just understand the voltages I tell it and to display the AFR accordingly so I shouldn't notice any visual changes.