Too little cotton perhaps? Is your coil resistance high or floating all over the place? Whenever I had weak coils, it was probably due to poor coil lead contact at the screw heads.
There's a new kid in town though. Big clouds, better heat and flavor transfer. I've rewicked everything with this, even T3s and I can tell you there wont be any stealth vaping anymore......big clouds!
Rayon Wicks