Hi, very new to tuning here, so apologies if there isn't enough detail or if i've missed something.

2004 TT 8N BAM 86k miles, Intake, Intercooler, sports cat, exhaust.  Stock everything else.  98RON, new fuel filter.  Chasing a lean spike and timing pull on WOT.

Log 1 is pre changes

Scaled up KFKHFM to increase fuelling, decreased LDRXN in the midrange to try stop the overboost.

Log 2 after, lean spike flattened but seems to be moved to the rest of the curve and no change in timing pull.  Car feels like it falls on its face around 4k.  Closed loop isn't working as i'm randomly getting O2 heater codes (even thought the O2 sensor is new and seems to be reading ok?).

Any guidance on where i should look next (and why) would be greatly appreciated.  Thanks in advance.

Log lambda control, you just have actual vs request right now. Knock correction is pulling 11.5* during your full throttle. Not enough data to say for sure but you either have a fuel delivery issue, or fueling is calibrated bad. Can't be sure on that unless you log lambda control. Doesn't look like lambda control is dropping out, more looks like you are not meeting request. The other option is put a fuel pressure gauge on the supply fuel hose and monitor fuel pressure at full throttle. If fuel pressure goes up a little bit, then starts to drop, fuel pump or plugged fuel filter is the issue. If its the original fuel pump, odds are thats the problem, but logging lambda control or fuel pressure gauge to monitor fueling would confirm this.

I've not yet looked at your binary, but something is causing your lambda control το be disabled.
I'd not push the car, as you're essentially running lambda 1.0
The fact that your Injector duty cycle reaches 85% while making lambda 1.0 also increases the chances of your fuel delivery system having some issue, as nameless said.

I turned on post cat O2 as well as went through wiring with a finetooth comb this morning and Lambda is now tracking as requested.  Not sure what the actual factor was but it seems much happier now so I can start bumping up the boost again.

I am probably still due a fuel pump though as duty is 80% chasing 0.85 at 12psi.

Thanks for the help