Newly TT and AFR/Idle problems

ZMan82

I was wondering if anyone could shed some light on something I'm experiencing with my 2010 40th 370z. I recently had AAM's TT installed by a local performance shop, and tuned with UpRev. My problem is only with the AFR and low RPMs/idling. The car has been tuned so that the idle RPMs are around 1100rpm to account for the larger fuel injectors (DW 1000cc), but the AFR though normally fluctuation around the 14-15 mark, will spike to the 22 or so area for about 5 secs before settling back down. This is just while the car is in neutral only/clutch pressed in. When it jumps up like this, the car will vibrate rather violently and I can immediately smell what seems to be fuel. Today being the 3rd day with the car, it has now thrown an engine code as well, and happened during one of these many "spasms" of AFR.

Now I don't yet have a fuel return system, which is on order, as it was suggested that this could help with this, but I just wanted other's take on this perhaps being the only thing needed for a solution?

When under load, the car is excellent in terms of boost, power, etc... It is only at idle that concerns me.

Thanks!

Build info:
AAM TT Kit
DW 340LPH
DW 1000cc
UpRev Tune
Innovative wideband
Turbosmart eboost2