Bank 1 Random Lean WOT Issue

14Q60awdSPORT

Have a Q60(g37) but figure the 370z forum is more active and the platforms similar enough ill post here.

2014 AWD Q60 - 42k miles
My car all of a sudden started having this issues, I am boosted working on getting E-tuned, my latest revision I did several logs/pulls and drove for a few days everything perfectly fine, tune was pretty close to dialed in.
Then randomly out of nowhere I go to do a 3rd gear pull and car has no power, shifts to 4th and then takes off like its back to normal. Then once I slow down and come to a stop, I start hearing an odd tapping sound, sounds like its coming from the back of the engine area (hard to pin point).

The noise is not present in neutral, only in gear only between about 1900-2500 rpm its almost like an on off switch hitting 1900 and exiting 2500. If I coast and have rpm drop down through that RPM range it doesn't do it. So only in gear underload while accelerating. The noise is pretty quite but without the radio on its noticeable. Besides the odd noise it drives good with good AFRs in certain scenarios like slight incline low throttle it might stumble or hesitate a little, but otherwise drives fine besides at WOT.

Now every time I do a pull its breaking up and backfiring, I managed to get a log of it and bank 1 is randomly going lean, looks like its only happening at higher RPM, as I didn't see this between 3k-5700 rpm.

Besides the supercharger nothing has really changed on the car in 2+ months of daily driving it with no issues, the supercharger has been daily driving about 2 weeks no issues, until randomly this issue popped up.

I have catless res downpipes, but stock header. header to DP gasket should be good, hard to tell header to block though but its untouched still oem stock, Z1 coilpacks, NGK stock spark plugs both about 2k miles on them, new downstream 02 sensors, ported upper and lower manifold. ID 1300CC injectors. Currently no CEL or DTC codes, and fuel pressure is good, have a fuel pressure and boost gauge independent of ecutek.
2 or so month ago I had injectors flow tested and leakdown tested and they where fine.

Car has always been on the richer side with trims pulling a little fuel typically at 85-95% or -5 to -15 not ideal but not terrible, Idle about -5 to -8, cruising 2500rpm is 0 to -5 but other scenarios like low RPM low load will swing it to -15 to -20, coasting downhill for example.

not sure if the odd tapping and the bank 1 lean are related or coincidental or what.

Attached Images

AFR Issue.PNG (68.4 KB, 5 views)