now just remember I'm new at this thing also but maybe cos as the popping is happening with no throttle open as you are decelerating, you are only lean due to you air idle screw needing adjustment out. From what I've read, the tbs (which I have also) are effective midrange therefore having no impact on deceleration. Just how I see it and am happy if someone tells me I'm talking crap.

Staintune Pipes, K&N Pods, 45 pilots, TBS needles and 145 mains.