2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 114Get this manual

2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 114

ENGINE Engine Has Low Power Spark plug fouled Cylinder, piston, ring, or valve wear or damage (check compression) PVT not
faultylean condition Exhaust system air leaks Ignition system faulty: Spark plug cap crackedbroken Ignition coil faulty Ignition
or kill switch circuit faulty Ignition timing incorrect Sheared flywheel key Poor connections in ignition system System wiring
wet Valve sticking Air leaks in intake Lean condition Cooling System Overheating Low coolant level Air in cooling system
Wrong type of coolant Faulty pressure cap or system leaks Restricted system (mud or debris in radiator fins or restriction
to air flow, passages blocked in radiator, lines, pump, or water jacket) Lean mixture (restricted jets, vents, fuel pump
or fuel valve) Fuel pump output weak Restricted radiator (internally or cooling fins) Water pump failure Cooling system restriction
Cooling fan inoperative or turning too slowly (perform current draw test) Ignition timing misadjusted Low oil level Spark
plug incorrect heat range Faulty hot light circuit Thermostat stuck closed or not opening completely Possible loose or missing