2010 Polaris Sportsman 850 Service Manual, Page 63Get this manual
ELECTRONIC FUEL INJECTION Injector leakage is very unlikely, but in rare instances it can be internal (past the tip of the valve needle), or external (weeping around the injector body)The loss of system pressure from the leakage can cause hot restart problems and longer cranking timesInjector problems due to dirt or clogging are unlikely due to the design of the injectors, the high fuel pressure, the use of filters and the detergent additives in the gasolineSymptoms that could be caused by dirtyclogged injectors include rough idle, hesitationstumble during acceleration, or triggering of fault codes related to fuel deliveryInjector clogging is usually caused by buildup of deposits on the director plate, restricting the flow of fuel, resulting in poor spray patternSome contributing factors to injector clogging include; dirty air filters, higher than normal operating temperatures, short operating intervals and dirty, incorrect, or poor quality fuelCleaning of clogged injectors is not recommended; they should be replacedAdditives and higher grades of fuel can be used as preventative measure if clogging has been problem6789Carefully disconnect the ECU by pulling the tab out while pulling down on the connectorLoosen the hose clamp retaining the intake boot to the intake plenum and remove the bootLift up on the air box and turn it sideways to gain access to the fuel rail and fuel injectorsThoroughly clean the area around the fuel rail and injectors