My boys 08 LTZ 400 will start with the choke on and idle fast,as soon as you touch the throttle it stops.if you mess with the choke and give it some gas slow it will rev up some and back fire,then quits.Could this be a throttle position sensor problem?A month ago the choke cable came unhooked at the lever,hooked it back up and it was very hard to move,also noticed it did not move as far as before.found corrosion where it goes inside the carb.cleaned this out put everything back together and it ran fine for about a week.then all at once it started backfiring and was hard to start.can anybody help me out?

 

Sounds as if the carb needs a rebuild but I find that kinda odd for a 08 already. Well if all else fails you can pick up a new carb for 350.00 from bike bandit. Sorry I am not much help!
2008 Suzuki ATV Parts for LT F400, OEM and Aftermarket at BikeBandit.com

 

if you go with the aftermarket route, check out sudco, they can hook you up with a carb for CHEAP.

 

also, being on 08, wouldnt your warranty still be of some help? (i have oldschool bikes and have no idea how those waranties work nowadays)

but of course, give the carb a good cleaning and rebuild before you drop alot of money into it.