I have one of our Billy Goat Force blowers with the 13hp honda on it that tipped over in the truck last year and no one realized it until the next stop. Well it wouldnt start up and when it finnally did it blew all kinds of smoke so I took spark plug out, pulled on starter rope to shoot any oil that was in there out, replaced with new spark plug, replace air filters that were aslo soaked with oil and gas and changed the oil again too.. Now it starts fine, blows no smoke and runs well...for about a minute then on its own idles down to next to nothing and on its own throttles up again. This is such a pain tho cause it happens in 1 to 2 minute intervals. Any ideas on what is happening and how to fix it???