what size wick are you using? are you using the imeo approved wick? i found with the cheap wick from most sites that i would get gave a slight leak, but after buying the good wick from cov i have had zero problems and ive been building bishops dual coil for 6 months with no problems. im sure you have taken these measures, but make sure you screw down the rebuildable tight so the oring makes a seal. second, make sure the lock ring is secure. and make sure you have enough meat on your wick to fill the channel, not enough wick will allow juice to pass threw and might leak down center pin. at first i had problems with leaks and gurgling and it was user error, not to say your doing something wrong, but have faith, imeo will make sure your vaping penny properly