I just bought a new 800 efi sportmans.
When it warms up the throttle shaft was sticking in the throttle body making it run at 2000 to 3000 rpm at times.
The throttle cable would come back to the idle postion but the throttle blade and shaft stuck open just a bit making it run 2000 to 3000 rpm.
So I new the throttle cable was ok.
Some times u could stab the throttle and it would come back to idle and other times it would just die as the etc would kill the engine.
Called the dealer and they never herd of such a thing......right.....lol
What is happening is when it warms up the throttle shaft is sticking in the throttle bore. This could happen to if it was cold to.....but mine is doing it after it warms up.
You can feel it sticking in the the throttle lever as it is not as smooth as it should be.
So I took the seat off.....the right side panel.....take foam off plastic air pipes....take off small rubber hose to air box......use screw driver after you remover clamp and pry hose off....was a sob getting it off....spray wd 40 in hose and use finger to spread it around inside hose to help install and next time hope it comes off more easy.....loosen clamp at throttle body......remove top half of air cleaner box and plastic intake.....take bolts outa air cleaner box....lift back of box up some just enough to remove rubber hose from throttle body and sit rubber intake hose on top of throttle body.
I had the engine warm when I did this as this was when it was happening.
Put finger in throttle body till u find throttle blade......now back r finger off a bit then apply a little throttle by the way of throttle lever then release....new see if you finger can close the throttle blade any amount....mine moved like .010 inch....not much but enough to cause high idle.....you can also close the throttle blade by hand till it seats....get a mirror and look at were it is closed completly and then apply a little throttle by using throttle lever on handle bar then release....I could see the throttle shaft and blade not completly closing.....used my finger again and could move throttle blade to close it......note make sure you adjust the throttle cable freeplay to about 1/4 inch so you don't get a false reading....you can adjust it to what the manual says about 1/6 to 1/8 after you are done.....now get your wd40 out and spray on each side of throttle shaft were it goes inside the throttle body.....wait a few minutes then work throttle shaft with your throttle lever on handlebar....I noticed a big difference right away.....in mirror could see the throttle blade completly closeing like it should be....i did this over and over several times....then let it set for 24 hours.....then after 24 hours hold throttle blade wide open with lever on handlebar and take your other finger and see if you can move throttle blade right or left.....it will be only soooo slight so you need to sentive to this....maybe it will move only .002 or .003 inch but u can feel it if r good at this.....mine moved this much.....I sprayed it again and worked the throttle lever open to closed like 50 times and with mirror I could see it was completly closing and to make sure I used my finger after it was closed and it would not close anymore....My machine was made 7 months ago and sat there for 7 months before it was used and new.
Now why is this doing it?.....3 reasons imo....in a carb version you have gas going by the throttls blade and shaft to keep it lubed.....in efi all you have is air and if the fit is tight as in my new machine it may take time to loosen up a bit.....but I could see this happening anytime....also imo they could use a more spring pressure on the throttle blade to help closing....and I don't no if they use special coatings or bushing as I could not see any from just looking inside the throttle body.
I could see this happening if you have not used the machine in awhile so maybe foging it with polaris fog stuff in the polaris owner's manual.....I have a repair manual on order which any diy needs.
After putting it all back together....setting the throttle lever as in manual....I started it up.....it ran rough and smoked from the wd40 for a minute or to....then it idled to 1200 and the throttle blade does not stick anymore.
Dealer said it should idle at 1200 + or - 150 rpm....I have to take there word for it till I get my manual.
Also there was no trouble codes set when it idled at 2000 to 3000 rpm.
And after riding it checked trouble codes again and none were set so am good to go.
Hopefully I won't have to do this again....and I have noticed the more it runs it seems the throttle lever is getting smoother all the time.
Hope this helps some people as I have seen some info on this...

Art

 

Throttle plates can stick even if air filters are kept clean,just a little gas and dirt over a period of time can varnish around plate causing it to stick! wd-40 like you used or lightly spray carb cleaner around plate. Same thing I have to do with my my truck butterfly valve about every 30,000 miles or so! Dirt and varnished gas cause plate to stick and I feel it through the pedal,have to stab at petal to unstick(kinda dangerous) until I clean plate again. As far as carb atvs on the full size Polaris machines,there's no plate to worry about. Only the slide,usually doesn't stick unless setting for months! Dealer fairly correct on idle,1180-1220 rpms ,but all machines will vary a little. Dont think i've had any two machines idle exactly the same. All depends on inital tps setting and throttle plate idle adjustment from factory!