I need your thoughts on this problem that happened to me today. I was headed out flying and pre-heated my engine for apprx. 1 hour and the engine was not that warm before starting. I started the engine and let it run for about 5 minutes with the carb heat off at about 700-800 rpm. Then I started taxing down the runway which had about 3 inches of powder snow using about 1100-1200 rpm. The strip is 1000ft long and as I proceded down the carb heat was off. The engine quit just as I reached the end of the strip, so I primed it once (the primer felt harder than usual to push) and started the engine again, and again it ran and quit. Primered it again and hopped in and brought it up to 1500rpm and pull the carb heat and the rpm drop about 50 rpm, but the engine keep running. I ran the engine on the ground for about 15 minutes, but it seemed I was not getting a full 100rpm drop when I pulled my carb heat. The engine was just creeping up 100 degrees when I turned it off and put it away. Any ideas or just bad carb ice???