2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 170Get this manual

2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 170

500 EFI FUEL SYSTEM FUEL SYSTEM TROUBLESHOOTING FUEL STARVATIONLEAN MIXTURE The correct position of the throttle body idle
improperly adjusted, routed incorrectly Failed Sensor or disconnected wiring IAC stuck or inoperative Intake air leak Symptom:
Idle Too Low (if less than 900 RPM when engine is warm) Plugged air filter Leaking injector (rich condition) Belt dragging
Throttle stop screw tamperingreplace throttle body Failed Sensor or disconnected wiring Symptom: Erratic Idle Throttle cable
incorrectly adjusted Air Leaks, dirty injector TPS damaged or adjusted Tight valves Belt dragging Dirty air cleaner Engine
worn Spark Plug fouled Throttle stop screw tamperingreplace throttle body Failed Sensor or disconnected wiring RICH MIXTURE
Symptoms: Fouls spark plugs, black, sooty exhaust smoke, rough idle, poor fuel economy, engine runs rough misses, poor performance,
bog, engine loads up, backfire Air intake restricted (inspect intake duct) Air filter dirtyplugged Poor fuel quality (old
fuel) Fouled spark plug TPS setting incorrect Injector failure Failed Sensor or disconnected wiring Throttle stop screw tamperingreplace