A little help, please...

My 01 Sportsman is having problems. It starts fine, idles fine, and runs fine at very low speeds, but if you get on the throttle, either in gear or in neutral, it sounds like it is dying. Replace the spark plug and air filter, but nothing... it has been at the dealer's for a week and they have no clue... any suggestions?

 

If it starts fine, idles fine and rejects application of throttle it sounds like a fuel starvation problem or a misadjusted ETC control.

Check the following:

kinks/blockage in the carburetor vent tubes

water in the fuel bowl

improperly adjusted ETC control

plugged pilot or main jet

low fuel level in the carburetor caused by improper float settings

These are the obvious easy things. Ask your dealer if he has performed these tests. Good luck[img]i/expressions/face-icon-small-wink.gif[/img]

 

Check all that Thor suggested.
One thing to try. Hold down the override button. Now will it rev up?? If so, it is likely either the transmission range sensor or the rev limiter.