You can get those coils to work better. It seems that some of the BVC coils have an airflow issue. It is more prevalent on the 1.6 than the 1.8 because of the coil size. To fix them, you need only a partially unfolded paperclip. You should be able to stick the straightened paper clip straight through the middle of the BVC coil. If you start from the open end, you should see the tip of the paperclip down through that tiny side-ways hole on the base of the positive connector piece. -If your paperclip doesn't go all the way through, you have to clear a path so it will. You must be careful. You want to work the paperclip so it pushes the ceramic wick away from the areas that are blocking airflow. Just be gentle and it will work. -You can test the airflow of the coil even before you put it on the Nautilus. Just blow through it like you would a whistle. You will know if the coil needs to be fixed. The whole process only takes a few minutes. You can make almost every coil work well for you this way.