CSC RX3 - Electronic Fuel Injection System; Fuel Injection System Operating Principles

CSCRX3ServiceManual
www.CSCMotorcycles.com
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ElectronicFuelInjectionSystem
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Themainfunctionoftheelectronicfuelinjectionsystemistoatomizeandinjectfuelintothe
combustionchamber.
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FuelInjectionSystemOperatingPrinciples
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TheelectronicfuelinjectionsystemconsistsoftheECU,injectornozzle,throttlevalveassembly,intake
airtemperature,integrationpressuresensor,enginetemperaturesensor,
ignitioncoil,crankshaft
positionsensor,oilpumpassemblyandoxygensensor.
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Theengineelectronicfuelinjectionmanagementsystempreciselycontrolsthemixtureratioofairand
fuelconductedintotheenginecylinder,thecombustionprocessandtheexhaustgasconversionto
optimizeengineperformance.Thesystemcontrolsalsocontrolsemission
levels.
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TheECUisasinglechip‐basedmicroprocessor.TheECUrecognizesworkingconditionsoftheengine
afteranalyzingitthroughsensorsinstalledontheengineandotherlocations.TheECUpreciselycontrols
theengineandcorrespondingsystems.
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Theenginerpmandcrankanglesensorisamagneto‐electricsensor
throughwhichthesystemcan
determinethelocationandspeedofthecrankshaft.
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Thecrankanglesensor,whichisinstalledontheclutchcoverofthetransmission,workswiththegearof
theflywheel.
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TheMAPsensorisinstalledontheinletpipetomeasurethepressure.TheECUjudgesthe
airamount
enteredintotheenginethroughthissignal.
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TheMAPsensorconsistsofasealedelasticmembraneandaferromagneticcore,bothofwhichare
placedpreciselyinsidethecoil.Whenitsensespressure,theMAPwillgeneratea0～5Voutputsignalin
directproportiontoinputpressure.
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Thethrottleplatepositionsensor,alinearvariableresistorstructureinstalledonthethrottlevalvebody
assembly, sharesthesameaxlewiththrottlelinkageandthrottlevalveanditsslideendisdrivenbythe
throttleplateaxle.
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TheresistancesignalgiventotheECUfromthesensorvariesfrom
throttleopeningtothrottleopening.
Thesystemwilljudgetheengine’sreal‐timeloadinganddynamicchangeaccordingtotheoutputsignal
valueandtherateofchange,givingprecisecontroltotheengine.
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Theintakeairtemperaturesensorisinstalledontheairintakesystemarticulatingpipetodetect
theair
temperatureenteredintotheengine,anditalsoadoptsnegativetemperaturecoefficientthermistorsas
itssensingelements.
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Theairtemperaturechangedirectlyaffectsitsdensity.Therefore,theintakeairtemperaturesensoris
oneofthemostimportantparameterstocalculatetheactualairamountenteredintothecylinder.