I am having two odd lean conditions and I'm not certain they are related.
The first:
after extended engine braking (like approaching a red light thats still far away) once I press the clutch in the idle will drop hard (~500rpm), may even want to stall, AFR pegs lean. I have to blip the throttle a couple times to get it back. You can see in the log that the IDC drops to 0% during decel, the idle switch is on, and once a press the clutch the idle drops like a rock. You can see me blip the throttle a couple times. Apparently I killed the log before the afr returned to 14.7, but the idle did recover. It seems that this only starts to happen after the engine is warm. I didn't want to muddy the picture too much, but the stock o2 gauges are behaving as expected and fuel trims are >10% (I know have those within 2% and the issue persists). I find it interesting that the ISC doesn't try to correct the problem until I start to blip the throttle.
lean_after_engine_brake.png
The second:
very occasionally on light acceleration I'll get a blip of lean with a loss of power. What I find interesting is that the IDC drops during that time as well, almost like the ECU wanted it to happen...
lean_spikes.png
EDIT - Possible 3rd issue, although perhaps its related to the second. Occasionally during cruise the car goes full lean (>18AFR). It will eventually recover on its own. It will also temporarily recover once getting into boost (or perhaps into open-loop). The whole event will last 10 seconds or so, and after coming back out of boost it will likely go back to being lean again.
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