What would cause an 05 M7 EFi to bog every now and then. There are times when you hit the throttle it will just bog bad. If you release the throttle and feather it a couple times it will take off and go good. This bog happens from stand still and when in motion. When I road the sled last year there was no problem but this year it is bogging. I was thinking maybe the fuel but I have ran 2.5 tanks of new fuel thru it.