Really doesn't matter how old the coil is. If too much power has been applied and some of the cotton burns away, as in dry hit, any coil is prone to leak after that.
As you work up the power on a new coil or device, at the first sign of bad taste or dryness back off the power a bit and give the wick a minute to catch up before hitting it again. At least this is how I've been doing it. YMMV.