Hi, I went to fire up my sled after it sat all summer and the only way it will start is if i give it some throttle. Once it finally starts after many pulls it shuts down below 3500 rpm's. I never put fuel treatment before I stored it so I drained the fuel and added fresh gas with some injector cleaner. We just got over a foot of snow so I took it out, it takes full and mid throttle just fine, it just wont go below 3500. Any ideas would be appreciated. I was thinking it could be a mouse nest in the air box but it still has all the mesh screening and fine filter at the inlet, and besides that airbox doesnt look like it's too fun to take out.