well im kinda choked up here. Go to ride today start up the sled runs idles fine after a minute starts to bog then give it a lil gas and just sounds like its running on one cylinder and then backfires couple times then with one big backfire it dies and it does this a couple time and now wont start again. Took the carbs off and check the jets to see if they were clogged or frozen. changed plugs. still nothin fires once everyonce and a while. it is a 04 440. Some quick help would be nice because i think the hood might get an axe thru it. If it helps yesterday i filled up in the snow so maybe it got condensation in the tank but i am running iso and have been for a while. hopefully this is not a expensive fix.