i have an 04 f6 sp. 460 jets. when i carve deep powder, after some good turns the sled sputters and starts to die, i have to pull over and stay on the gas so it wont die. after a few moments its ok. after a long run and stop, it idles high for a few moments then idles down.one plug is very light brown (tan)- the other is light grey. any help is appreciated. thanks.