That is definitely the issue you're having RepentWhen I ran 2.0 ohms @ 3.7V in the iAtty, it would gunk up within a day. Running 1.2 ohm @ 3.7 volts, I have been running 7 days now, still vaping great. No noticeable gunk buildup running a sweet rice krispity treat juice from KBV custom mixed to 50/50 PG/VG @ 24mg. The juice in the tank is not getting darker yet which is usually my clue that it's time to clean the coil again.
In case anyone is interested. I finally got that 1.8 ohm 32ga kanthal a-1 coil I was talking about to "pop". It was running for a good 6 weeks or so so I wanted to see just how much more it could take. I emptied everything and let it dry burn for close to 5 minutes (dunking in water every now and again to keep the delrin from getting overheated and cracking or melting). I thought the battery was going to give before the coil didIt's really good stuff!
And what are you using for wick in it?