if your coil start to have burnt taste within short using time，it may caused by these points：
1.your vaping is too frequently
2.vaping setting is improper
3.you didn't prime coil before vaping
4.Ejuice is not enough in the core.
1.Please try to inhale for several puffs without powering-on while using a new core or let the tank sits for about 15 mins.
2.Please prime the coil with low wattage for the first several puffs.