my xt has been doing fine up until now.went to take her out for a run and cant get her to start,i have spark and fuel is getting to carb.i have not needed to adj.the high and low at all as the truck has been running great so far.no idle adj.needed either.i have had good luck with two stroke and nitro engines and I don't want to mess around with settings if I don't have to.i also changed the plug.what do you guys think.