Hey dude, long time no see. Good to see you're still a KAT guy. Just so I understand this, you can be at full boost, partial throttle say 3/4 and no leaning out? What about a controlled application of throttle until you reach WOT, by that I mean don't just floor it, take like a full 2 seconds to reach WOT. See if it goes lean then.
Is the TPS loose or anything? Disconnect and reconnect that dude just to marry the pins again.
15 is crazy lean dude, be very careful.
Due process is very important - Right after they are waterboarded.