2010 Polaris Sportsman 850 Service Manual, Page 83Get this manual
ELECTRONIC FUEL INJECTION FUEL SYSTEM TROUBLESHOOTING
The correct position of the throttle body stop screw is established and set at the factoryDO NOT remove the tamper proof cap to adjust the throttle body stop screw or alter its position in any mannerThe stop screw controls the air flow calibration of the throttle body
Poor Idle
Symptom: Idle Too High (If greater than 1400 RPM when engine is warm) Throttle stop screw tampering Throttle cable sticking, improperly adjusted, routed incorrectly Failed sensor or disconnected wiring IAC stuck or inoperative Intake air leak Symptom: Idle Too Low (if less than 1100 RPM when engine is warm) Plugged air filter Leaking injector (rich condition) Belt dragging Throttle stop screw tampering Failed sensor or disconnected wiring Symptom: Erratic Idle Throttle cable incorrectly adjusted Air Leaks, dirty injector TPS damaged or misadjusted Tight valves Belt dragging Dirty air cleaner Engine worn Spark Plug fouled Throttle stop screw tampering Failed sensor or disconnected wiring