潍柴电喷案例（weichai efi case）

潍柴电喷案例（WEICHAIEFICASE）WEIFANG336AND375EDC7CASECOMMONFAULTTYPESFAULT1DIESELENGINEDOESNOTSTARTORSTARTDIFFICULTFAULTTWOENGINEPOWERSHORTAGEMAXIMUMSPEED150016001700FAULTTHREEENGINE1000RPMASSOCIATEDWITHTHEACCELERATORPEDALFAULTFOURLIMPHOMEENGINEMAXIMUMSPEEDCANONLYREACH1500FAULTFIVEUNSTABLECRUISEFAULTSIXFLASHCODELIGHTISALWAYSONFAULTSEVENSUDDENLYFLAMEOUTDURINGOPERATIONFAULT1DIESELENGINEDOESNOTSTARTORSTARTADONOTSTARTTHEDIESELENGINEISACOMPRESSIONIGNITIONINTERNALCOMBUSTIONENGINESMOOTHSTARTINGOFDIESELENGINENOTONLYALARGEAMOUNTOFFUELISREQUIREDTOBEINJECTEDINTOTHECYLINDERAFTERSUFFICIENTATOMIZATIONITALSOREQUIRESTHATTHEAIRINTHECYLINDERBECOMPRESSEDTOACERTAINTEMPERATUREANDPRESSUREONLYINTHISWAYCANTHEDIESELENGINEBESPONTANEOUSCOMBUSTIONTHEREFORE,THEDIESELENGINECANNOTSTARTSMOOTHLYTHEREASONSAREGENERALLYONTHESTARTINGSYSTEM,THEELECTRONICALLYCONTROLLEDFUELSYSTEM,THEINTAKEANDEXHAUSTSYSTEM,ORTHEDIESELENGINECLEARANCECUSTOMERMAYBEACCOMPANIEDBYFAILURECHARACTERISTICSANALYZEANDJUDGEACCORDINGTOTHEPROCEDURE11STARTERDOESNOTWORKFORTHESTARTER,CONTROLLEDBYTHEECUVEHICLEATBOOTTIME,ECUCHECKSTHENEUTRALSIGNALFIRSTTHEN,ACURRENTISSTARTEDTODRIVETHESTARTINGRELAYAFTERTHERELAYISSWITCHEDON,THEBATTERYDRIVESTHESTARTERTHEREARESEVERALFACTORSINTHEINSPECTIONNEUTRALSWITCH,STARTERRELAY,BATTERY,ANDTHEPARKINGSWITCH01CHECKWHETHERITISINNEUTRALPOSITION01CHECKTHEPOSITIONOFTHEPARKINGSWITCHSHOULDBEINASTATEOFDISCONNECTION0,1CHECKTHENEUTRALSWITCHUSUALLYMOUNTEDONTHETRANSMISSIONANDWHETHERTHEWIRINGISINGOODCONDITIONTRYUSINGEMERGENCYSTARTINGIGNITIONSWITCHCONTINUESFORMORETHAN5SECONDSTRANSMISSIONCASENEUTRALSWITCHDOWNSTOPSWITCH01CHECKWHETHERTHEBATTERYVOLTAGEISTOOLOWTODRIVETHESTARTER0,1STARTERRELAYSANDWIRINGAREINGOODCONDITION01CHECKTHATTHESTARTERISBURNEDOUT01ISTHEIGNITIONSWITCHANDTHESTARTERSWITCHOUTOFORDERIGNITIONKEYSWITCHCASE1SHAANXIWP10336TRACTORENGINECANNOTBESTARTEDSTARTERISNOTTURNEDINSPECTIONPROCESSWHENTHEKEYSWITCHPOSITIONISREACHEDSELFCHECKINGLAMPSELFTESTNOTETHATTHEECUISPOWEREDONCHECKTHE140LINEVOLTAGECHECKTHEIGNITIONCIRCUIT161WITHOUTVOLTAGEANDFINDTHATTHEINSURANCEISBURNTOUTAFTERREPLACINGANINSURANCE,ELECTRIFYBUTSTILLUNABLETOSTART,ANDREPORTED“MAINRELAYERROR“RECONNECTTHEMAINRELAYAFTERWIRINGANDTROUBLESHOOTCASE2SHAANQITRACTORWP10336THEENGINEDOESNTSTARTTHESTARTERDOESNTTURNINSPECTIONPROCESSWHENYOUREACHTHEKEYSWITCHPOSITION,CHECKTHELAMPSELFCHECKNOTETHATTHEECUISPOWEREDON140AND161WIRINGHAVEVOLTAGEOUTPUT,RELAY137LINESHAVEVOLTAGEPERMEABILITYBUTTHE151LINEISNOTGROUNDEDLOOPCANNOTBEFORMEDTOSEPARATE151GROUNDLINE,THENORMALSTARTCASE3SHAANQITRACTORWP10336THEENGINEDOESNTSTARTTHESTARTERDOESNTTURNINSPECTIONPROCESSWHENTHEKEYSWITCHPOSITIONISREACHED,THESELFCHECKINGLAMPISNOTSELFCHECKINGNOTETHATECUISNOTPOWEREDON140AND161HAVEVOLTAGEDETECTIONOFTWOPUBLICHIGHENDLINES,104AND203ARENOVOLTAGEOUTPUT,PRELIMINARYJUDGMENTECUINTERNALDAMAGEAFTEREXCHANGINGECU,THEECUFAULTISCONFIRMEDTROUBLESHOOTINGAFTERREPLACINGNEWECUCASE4SHAANQITRACTORWP10336THEENGINECANNOTSTARTSTARTERISNOTTURNEDINSPECTIONPROCESSWHENTHEKEYSWITCHPOSITIONISREACHEDSELFCHECKINGLAMPDOESNOTSELFCHECKNOTETHATECUISNOTPOWEREDONINVESTIGATIONFOUNDTHATTHEVEHICLELINEBURNEDOUT,THEUSERINTHEBATTERYLINEWILLBEPOSITIVEANDNEGATIVECOUNTERBURNOUTLINESANDECU12RAILPRESSURECANNOTBEESTABLISHEDSTARTERNORMAL,BUTCANNOTSTARTDATASTREAMACTUALRAILPRESSURECOMMONRAILSYSTEMREQUIRESHIGHERFUELCIRCUITLOWPRESSUREOILCIRCUITOILTANKROUGHFILTERFINEFILTRATION,RETURNOIL,HIGHPRESSUREOILCIRCUITHIGHPRESSUREOILCOMMONRAILHIGHPRESSURETUBINGINJECTORMUSTENSUREAIRTIGHTANYLINKHASAPROBLEMRAILPRESSURECANNOTBEESTABLISHEDPROPERLYPROMPTTHEHOSTPLANTTOATTACHGREATIMPORTANCETOTHEENTIREFUELCIRCUITNOTETHEFIRSTSTARTOFTHEVEHICLEMUSTBECARRIEDOUTINTHELOWPRESSUREOILCIRCUITANDTHEHIGHPRESSURECIRCUITFOREXHAUSTANDOILFILLINGINSPECTIONMETHOD01CHECKTANKLEVELISTOOLOW01CHECKHANDPUMPISWORKINGPROPERLY0,1CHECKTHEOILCIRCUITISCLEAR,CHECKTHEDIESELFILTERISBLOCKED,ITISRECOMMENDEDTOREPLACETHEDIESELFILTERINSPECTIONMETHODRELEASETHEFILTEROUTLETBOLT,DRIVETHEDIESELENGINEWITHTHESTARTER,ANDCHECKWHETHERTHEDIESELOILISEJECTEDORDISCHARGEDIFONLYASMALLAMOUNTOFDIESELOILISDISCHARGED,THEFILTERCORECANBEBLOCKED0,1,CHECKWHETHERTHELOWPRESSUREAIRCIRCUIT,SIDEAIRSOMETIMESLOWPRESSUREOILLEAKAGEISNOTOBVIOUS,NEEDTOBECAREFULLYCHECKEDEXHAUSTMAINLYDRAINTHEAIRINSIDELOOSENBOLTSONTHEAIRSTRAINER,HANDPRESSUREPUMPROUGHFILTERONTHEHAND,UNTILTHEAIRBOLTCONTINUEDOILSOFARHANDPRESSUREPUMPBLEEDBOLTOILRETURNHOLLOWBOLT0,1,LOWPRESSURECIRCUIT,AIREXHAUSTSTILLCANNOTSTARTTHEDIESELENGINE,THENDETERMINETHEHIGHPRESSUREAIRCIRCUITITALSONEEDSTOEXHAUSTTHEAIROFTHEHIGHPRESSURECIRCUITEXHAUSTMETHODLOOSENACYLINDERHIGHPRESSURETUBINGDRIVETHEDIESELENGINEWITHASTARTERUNTILTHEHIGHPRESSUREPIPECONTINUESTORUNOUTITISNOTRECOMMENDEDTOREMOVETHEHIGHPRESSURETUBINGJOINTSFREQUENTLY01CHECKTHEHIGHPRESSURECIRCUITFORLEAKSINVESTIGATIONMETHODIFTHEHIGHPRESSUREAIRPIPEISDISCHARGED,THERAILPRESSURECANNOTBEESTABLISHED,THENITISNECESSARYTOCONSIDERWHETHERTHEINJECTORFAULTTHEWP10SERIESCANDISASSEMBLETHEINJECTORRETURNPIPEANDDRIVEWITHTHESTARTERTOOBSERVETHEABNORMALRETURNUNDERNORMALCIRCUMSTANCESINFRONTOFTHECARTHEINJECTORSHOULDBEFREEOFOILANDGASIFTHEREISITCANBEJUDGEDASTHELEAKAGEOFTHEINJECTORUSUALLYDUETOOILPROBLEMS01CHECKWHETHERTHEINITIALVOLTAGEOFRAILPRESSURESENSORISAROUND05VORSETTHERAILPRESSUREIS350500BAR,IFNOTNORMAL,FIRSTCHECKTHECONNECTORISRELIABLEWITHOUTINSPECTIONEQUIPMENTUNPLUGTHERAILPRESSURESENSORCONNECTORANDTRYRESTARTING01CHECKTHATTHEFLOWMEASUREMENTUNITISINGOODCONDITION,UNPLUGTHECONNECTORANDTRYTOSTARTAGAINWHENTHECONNECTOROFTHEFLOWMEASURINGUNITISPULLEDOUT,WHENSTARTING,THEOILPUMPWILLSUPPLYOILTOTHECOMMONRAILPIPEWITHTHELARGESTOILSUPPLYNOTECHECKTHERAILPRESSUREBUILDUPCHECKTHECONDITIONOFRAILPRESSUREANDCONNECTTHEFAULTDIAGNOSISINSTRUMENTTHETRACKPRESSUREISDETERMINEDBYDETECTINGTHECHANGEOFRAILPRESSUREINTHEDATASTREAMUSUALLYTHETHEORETICALVALUEOFRAILPRESSURESHOULDBE0BARINTHECONDITIONOFNOTMOVINGBUTINTHEACTUALPROCESS10BAROR15BARMAYBEDETECTED,WHICHCANBETRIEDWITHOUTRAILPRESSUREWHENTHEVEHICLEISSTARTED,WHENTHERAILPRESSUREISBETWEEN350500BARECUCONTROLSINJECTORFUELINJECTIONITISPOSSIBLEFORTHEENGINETOSTARTINGENERAL,NOFAULTISREPORTED13MORETHANTHEFUELINJECTORSTUCK,CANNOTSTARTTHECARWHENTWOORMOREINJECTORSAPPEAR,TWOCARDSARESTUCKNOINJECTIONTIMECANNOTSTARTCASEYUTONGBUS,STARTERCANSTART,BUTTHEENGINECANNOTSTARTTHEDETECTIONCIRCUITISNORMALWHENTHESTARTERDRIVESTHERAILPRESSUREISUPTO400BARBUTSTILLCANNOTSTARTCHECKVALVE,PUSHRODANDVALVEARENORMALPRELIMINARYJUDGMENTOFMORETHANTWOINJECTORFAILUREAFTERSWITCHINGTHEINJECTORTROUBLESHOOTING14CRANKSHAFTSIGNALANDCAMSHAFTSIGNALLOSTSYNCHRONIZATIONSIGNALERRORTWOSPEEDSENSORSAREINSTALLEDONTHEDIESELENGINE,RESPECTIVELY,ONTHEFLYWHEELHOUSINGANDTHEHIGHPRESSUREOILPUMPTHEFUNCTIONSARECRANKSHAFTPOSITIONSENSORANDCYLINDERHEADSENSORTHEINJECTIONTIMINGOFANELECTRONICALLYCONTROLLEDENGINEDEPENDSONTHETWOSENSORSIFALLTWOSIGNALSARELOST,ADIESELENGINEWILLNOTSTARTCAMSHAFTSPEEDSENSORCRANKSHAFTROTATESPEEDSENSOR14LOSSOFCRANKSHAFTSIGNALANDCAMSHAFTSIGNALALLPOSSIBLELOSSOFTWOSIGNALSSENSORDAMAGE,WIRINGHARNESSSHORTCIRCUITOROPENCIRCUITTHESENSORISNOTFIRMLYFIXED,WHICHMAKESTHEGAPBETWEENTHESENSORANDTHEINDUCTIONTOOTHTOOLARGEORTOOSMALLUSUALLY105MMRULEOUTCHECKTHATTHESENSORISDAMAGEDANDWHETHERTHEWIRINGHARNESSISCONNECTEDPROPERLYWHETHERTHESENSORISLOOSEORNOTNOTETHEDISASSEMBLYANDASSEMBLYOFHIGHPRESSUREOILPUMPANDFLYWHEELSHALLBECARRIEDOUTINSTRICTACCORDANCEWITHTHERELEVANTPROCESSDOCUMENTSTOENSURETHESYNCHRONIZATIONOFTHESIGNALSTWODIESELENGINEDIFFICULTTOSTARTCAUSESANDTROUBLESHOOTINGOFDIESELENGINESTARTINGUPTHEDIESELENGINEDOESNOTRUNFORALONGTIMETHERETURNPIPESHALLBEEXTENDEDUNDERTHEDIESELLEVELLOWPRESSUREPIPELINEHASALITTLEAIREXHAUSTAIRTHECRANKSHAFTSPEEDSIGNALANDCAMSHAFTSIGNALARETOOWEAK,ANDTHESYNCHRONIZATIONTIMEISLONGREADJUSTTHEAMBIENTTEMPERATUREISTOOLOWANDTHEPREHEATERISINVALIDREPLACETHEPREHEATINGDEVICETHEQUALITYOFDIESELOILANDENGINEOILISTOOPOORTOMEETTHEREQUIREMENTSREPLACESTANDARDOILTHESTARTERORFLYWHEELGEARRINGGEARANDFLYWHEELRINGGEARREPLACETHESTARTERTHEPISTONRINGANDCYLINDERLINERWEARORVALVESEALTHEREPLACEMENTOFTHEPISTONRINGANDCYLINDERLINERORVALVESEATANDVALVETHEEXHAUSTBRAKEBUTTERFLYVALVESTUCKINTHECLOSEDPOSITION,RESULTINGINPOOREXHAUSTVALVEREPLACEMENTTOTHEFUELTANKINTOTHERETURNPIPEDIAMETERANDPRESSUREDOESNOTMEETTHEDESIGNREQUIREMENTSCASE1YUTONGBUSWP10336REFLECTSLONGSTARTINGTIMEMAINTENANCEPROCESSAFTERINSPECTION,THERAILPRESSUREBUILDUPPROCESSISTOOSLOWCHECKTHEOILCIRCUIT,FOUNDTHATTHELOWPRESSUREOILPIPELINEISTOOTHIN,THEINNERDIAMETEROFABOUT6MMMINIMUM12MMLESSTHANWEIFANGREQUIREMENTSALLLOWPRESSUREOILPIPESREQUIREDBYCUSTOMERSTOREPLACETHEOILPIPEINTHEFUELTANKWILLBEACTIVATEDAFTERREPLACEMENTCASE2SHAANXIWP10336TRACTOR,REFLECTINGTHEDIFFICULTTOSTARTOVERHAULPROCESSFOUNDTHATTHE“CRANKSIGNALISNOTCREDIBLE“FAULT,ANDTHEREISADIFFICULTSTARTFAULTITISFOUNDTHATTHEDIMENSIONOFTHEMOUNTINGHOLEOFTHECRANKSHAFTROTATIONSPEEDSENSORONTHEFLYWHEELHOUSINGISBIASEDCAUSESTHECRANKSHAFTSENSORTOBEINSTALLEDTHEDEVIATIONOFTHESIGNALHOLEONTHEFLYWHEELCAUSESTHECRANKSHAFTSIGNALTOBEUNRELIABLE“REPLACEFLYWHEELHOUSING,TROUBLESHOOTINGFAULTTWOINSUFFICIENTPOWEROFDIESELENGINE21INJECTORFAILURETHEINJECTORISOUTOFORDERGENERALLYDIVIDEDINTOMECHANICALANDWIRINGFAULT01MECHANICALFAILUREFORWHENTHENEEDLEVALVEISJAMMED,THENEEDLEVALVEISSTUCKINTHEINJECTORBECAUSETHEDIRTINTHEDIESELOILISMOREORTHEWATERISCORRODEDNOTICEECUMAYNOTBEWRONG01WIRINGFAULTFORBECAUSEOFVIBRATION,WEARANDTEAR,THEWIRINGISDISCONNECTEDORDIRECTLYCONNECTEDTOTHECYLINDERHEADANDSHORTEDTOTHEGROUNDECUWILLMAKEAMISTAKE01IDLEINSTABILITY,LISTENTOTHEABNORMALSOUNDOFDIESELENGINES01USINGBROKENCYLINDERMETHODORHIGHPRESSURETUBINGTACTILEMETHODTOJUDGE01USINGAFAULTDIAGNOSISINSTRUMENTTOSPEEDUPTESTDECISIONSCASEWP10290TRACTORREFLECTENGINEPOWERSHORTAGEUNABLE。OVERHAULPROCESSAFTERINVESTIGATIONTROUBLEFREECODEPRELIMINARYANALYSISISANOILCIRCUITORGASPATHFAILUREUSINGTHEFAULTDIAGNOSISINSTRUMENTTODO“ACCELERATEDTEST“,WEFOUNDTHEFIFTHCYLINDERWORKINGCAPACITYISPOOR,ANDAFTERFIFTHCYLINDERINJECTORREPLACEMENT,TROUBLESHOOTINGREMARKSDATAANALYSISOFACCELERATEDTESTINDATAANALYSIS,ADIFFERENCEOF50GENERALLYSPEAKING,ITCANBEREGARDEDASAFAIRLYGOODWORKABILITYADIFFERENCEOF50QUESTIONSNEEDTOBECONSIDEREDIFYOUCANTDO“ACCELERATEDTEST“,YOUCANMANUALLYJUDGETHEFAULTBYBREAKINGTHECYLINDERSPECIFICMETHODTURNOFFTHEPOWERSWITCH,DISCONNECTTHEINJECTORTERMINALYOUNEEDTOUSEINSULATINGTAPETOSEPARATETHETWOTHREADSRESPECTIVELYBREAKINGTESTSWEREPERFORMEDRESPECTIVELYMETHODSTHESAMEKINDOFEUROIIENGINE22WATERTEMPERATURE,ENGINEOILTEMPERATUREANDINLETTEMPERATUREARETOOHIGHWHENWATERTEMPERATURE,ENGINEOILTEMPERATUREANDAIRINLETTEMPERATUREARETOOHIGH,THEECUWILLPERMEATE,OVERHEAT,PROTECTANDLIMITTHEPOWEROFTHEENGINE0,1CAUSESTHEHIGHWATERTEMPERATUREANDTHEWAYTOREMOVEITTANKWATERSURFACEISTOOLOWCHECKWHETHERTHEREISWATERLEAKAGE,ADDWATERFANSPEEDISTOOSLOWORNOTTOTURNCHECKFANDRIVEPARTSWATERTANKBLOCKEDCHECKTANK,CLEANORREPAIRWATERPUMPBELTSLACKADJUSTTHETENSIONACCORDINGTOTHEREGULATIONWATERPUMPGASKETDAMAGEPUMPIMPELLERWEARCHECKANDREPAIRORREPLACETHETHERMOSTATFAILUREREPLACEMENTTHEWATERSEALFAILURELEAKAGEOFAIRCHECKPIPES,JOINTS,GASKETSANDSOONREPLACEDAMAGEDPARTSTHETEMPERATURESENSORDATATRANSMISSIONISNOTCORRECTREPLACESENSOR0,1MACHINEOILTEMPERATUREISTOOHIGHREASONSANDTROUBLESHOOTINGTHEOILLEVELOFTHEOILPANISLOWORLACKOFOILCHECKTHEOILLEVELANDTHEOILSPILLFIXANDREFUELHIGHWATERTEMPERATURECHECKTHEABOVECAUSESOFHIGHWATERTEMPERATURE,ANDEXCLUDETHEMENGINEOILCOOLERANDCOOLERCIRCULATIONCHECKANDCLEANUP0,1,THEREASONSFOREXCESSIVEINTAKETEMPERATUREANDTROUBLESHOOTINGMETHODSDROPINDEPRESSIONISDEPRESSEDBUTCAPACITY,HEATCAPACITYCHECKCOOLERINLETPRESSURE,TEMPERATURESENSORFAILURE,REPLACESENSOR23SMOKELIMITATIONTHEENGINEHASPRIORITYINSMOKEEXHAUSTWHENTHEREISAPROBLEMWITHTHEENTRYOFAIRLIMITINGTHEEFFECTOFSMOKEBYLIMITINGTHEAMOUNTOFFUELINJECTEDCASE1WP10375YUTONGBUSREFLECTSTHELACKOFENGINEPOWEROVERHAULPROCESSSITEINSPECTION,TROUBLEFREECODEPRELIMINARYANALYSISBELONGSTOTHEPROBLEMOFOILCIRCUITORGASPATHTHEDIAGNOSTICINSTRUMENTDETECTSTHEINTAKEPRESSUREATTHESTARTINGPOSITION,ANDTHEPRESSUREATIDLEISAPPROXIMATELY1012BARINSITUTHROTTLEINTAKEPRESSUREINTHEENDDIDNOTCHANGESIGNIFICANTLY,ABOUT11BARSUSPECTEDAIRFILTEROBSTRUCTIONORAIRINTAKESYSTEMLEAKSAFTERINVESTIGATION,TURBOCHARGERANDCENTRALASHCOOLERITWASFOUNDTHATTHEBOTTOMOFTHEINTERCOOLERCRACKEDABOUT15CMFOLLOWINGTHEDRAWINGSREMOVETHEINTERCOOLERALUMINUMAFTERTHAT,THEUSERTESTPOWERRETURNEDTONORMALCASE2AUMANWP10336TRACTORSLOWENGINESPEEDINCREASEESPECIALLYINTHEIDLE600RPMTO1500RPM,THESPEEDINCREASEISRELATIVELYSLOWANDINTHEPROCESSOFDRIVING,THEREISALSOALACKOFPOWERMAINTENANCEPROCESSTHEFIRSTINSPECTION,FOUNDNOFAULT,REPLUGSENSORTROUBLESHOOTINGAFTERDRIVINGFORAPERIODOFTIME,THESAMEFAULTOCCURSAFTERREEXAMINATION,THE“AIRPRESSURESENSOR“VOLTAGEISTOOLOW“TROUBLESHOOTINGAFTERCHANGINGINTAKEPRESSURESENSOR24FLOWMETERINGUNITFAILURETHEFLOWMETERINGUNITISTHEACTUATINGMECHANISMFORCONTROLLINGTHERAILPRESSUREINSTALLEDINTHEHIGHPRESSUREOILPUMP,AFTERITHASPROBLEMS,THEHIGHPRESSUREOILPUMPWILLSUPPLYTHECOMMONRAILPIPEWITHTHEGREATESTCAPACITYATTHISPOINT,THERELIEFVALVEONTHECOMMONRAILVALVEWILLGENERALLYOPEN,THEOPPORTUNITYTODIESELHAS“KNOCK“NOISETHEENGINEMAYHAVEAMAXIMUMSPEEDOFNOMORETHAN1700RPMTHEREISASIMILARPROBLEMWITHRAILPRESSURESENSORSFLOWMETERINGUNITCASE1SHAANXIWP10336NTRACTORINSUFFICIENTENGINEPOWERTHEMAXIMUMSPEEDCANONLYREACH1600RPMDETECTBYFAULTDIAGNOSISINSTRUMENTREPORT134TROUBLECODECOMMONRAILPIPEPRESSUREVALVEOPENFAULTDISCONNECTTHECOMMONRAILPIPEBACKANDFORTHTUBINGUSINGMINERALWATERBOTTLEOIL,STARTTHEENGINEITISFOUNDTHATOILHASBEENDISCHARGEDFROMTHECOMMONRAILRETURNPIPEATTHETIMEOFSTARTING,BUTONLYAFTERAFEWMINUTESCOMMONRAILPIPERETURNOILPIPEWITHOUTOILPHENOMENONACCORDINGTOCOMMONRAILTUBEPRINCIPLECOMMONRAILPIPEPRESSURELIMITINGVALVEISAMECHANICALVALVEFREEFROMECUCONTROLWHENTHEPIPEPRESSUREISGREATERTHAN1600BAR,THEPRESSURELIMITINGVALVEOPENSANALYSISOFTHEABOVEPHENOMENON,THEINITIALJUDGEMENTFORTHEMOMENTOFRAILPRESSUREISTOOHIGHMORETHAN1600BARTHECOMMONRAILPIPEPRESSURELIMITINGVALVEOPENSTHERETURNOILBECAUSETHERAILPRESSUREFLUCTUATESTOOMUCH,THEENGINEENTERSTHESETPROGRAMTHECOMMONRAILPIPEPRESSURERELIEFVALVESHOULDBENORMALSUSPECTISDAMAGETOTHEFLOWMETERINGUNITAFTERREPLACINGTHEOILPUMPTROUBLESHOOTINGBECAUSETHEUSERSOILQUALITYISNOTUPTOSTANDARD,TOOMUCHMOISTUREINTHEOIL,SOTHATTHEOILPUMPCORROSION,CAUSINGTHEFAULT25THELEAKAGEOFFUELPIPELEADSTOABNORMALFLUCTUATIONOFRAILPRESSUREINTHEPROCESSOFRUNNINGTHECAR,THEREWILLBEUNSTABLESPEED,THECARHASA“FORWARD“A“CHANNELING“PHENOMENON,ANDSOMETIMESFELTINTOTHEOILWITHOUT01EXCLUSIONMETHODSFIRST,POWEROFFFORONEMINUTE,RESTART,ANDIFTHEPROBLEMPERSISTS,CHECKFUELLINESEALANDREMOVE26SENSORFAILURETHEINTAKEPRESSURESENSORISAECUSENSORTHATISUSEDTOESTIMATETHEINTAKEINSTALLEDONTHEINTAKEPIPETHETEMPERATURESENSORISUSEDTODETERMINETHEHEATLOADOFTHEENGINEMOUNTEDONTHEOUTLETPIPETHERAILPRESSURESENSORISUSEDTODETECTTHEFUELPRESSUREONTHECOMMONRAILTUBEMOUNTEDONTHECOMMONRAILTUBETHESPEEDSENSORISUSEDTOMEASURETHESPEEDOFTHEWHOLEVEHICLENOTALLVEHICLESAREEQUIPPEDTHEVEHICLEWITHCRUISEMUSTBEINSTALLEDINSTALLEDONTHEGEARBOXREMOVALMETHODCHECKINTAKETEMPERATURE,PRESSURE,WATERTEMPERATURE,RAILPRESSURESENSORSEEIFTHECONNECTORISSECUREUSINGAFAULTDETECTORTODETECTDATASTREAMSSEEWHETHERTHETESTVALUEISTHESAMEASTHATOFTHEWHOLEVEHICLEMETERCASE1AUMANWP10336TRACTORENGINESPEEDINCREASEDSLOWLY,ESPECIALLYINTHEIDLE600RPMTO1500RPM,THESPEEDINCREASEISRELATIVELYSLOWANDINTHEPROCESSOFDRIVING,THEREISALSOALACKOFPOWEROVERHAULPROCESSFIRSTINSPECTIONDIDNOTFINDFAULT,RESEATINGSENSORTROUBLESHOOTINGAFTERDRIVINGFORAPERIODOFTIMETHESAMEFAULTOCCURREDAGAINRETESTTHEPRESSUREOFTHEAIRPRESSURESENSORISTOOLOW“TROUBLESHOOTINGAFTERREPLACINGTHEAIRPRESSURESENSORFAULTTHREEENGINE1000RPMTHEECUJUDGESTHELOADBYSIGNALSFROMTHEPEDALPOTENTIOMETERWHENTHEPEDALISOUTOFORDERFORSAFETYREASONS,THEECUWILLCONTROLTHEAUTOMATICIDLINGOFTHEDIESELENGINETO1000RPMREASONANALYSIS01ELECTRONICTHROTTLEPEDALLINELOOSEORWRONGREPLUGTHETHROTTLEORCHECKWHETHERTHEWIRINGISCORRECT,REWIRING01MEASURETHEVOLTAGEANDRESISTANCEOFTHEHIGHANDLOWENDOFTHEACCELERATORPEDAL,ANDDETERMINEWHETHERITISALINEPROBLEMNORMALLY,TWOHIGHENDVOLTAGESARE5VOLTSIFNOT5VOLTSYOUNEEDTOFINDLINEFAULTS01ELECTRONICTHROTTLECONNECTOR,WATERINLETTOOL,PLUGCONNECTOR,DRYANDRESTART0,1ACCELERATORPEDALQUALITYPROBLEMS,REPLACETHEACCELERATORPEDALNOTEYOUNEEDTHESAMETYPEOFACCELERATORWHENYOUCHANGETHETHROTTLECASE1HONGYANWP10290DUMPTRUCKWHENTHEVEHICLEISRUNNINGATIDLESPEEDAFTERAFEWMINUTES,THESPEEDWILLBEAUTOMATICALLYINCREASEDTO1000RPMANDTHEFAULTLIGHTISONINSPECTIONPROCESSAFTERCHECKING,THEENGINEREPORTEDTHATTHEACCELERATORPEDAL1AND2VOLTAGESIGNALSARENOTCREDIBLE“AFTERYOUDELETETHEFAULTCODE,STARTTHEENGINEATTHEBEGINNINGOFTHEOPERATIONNORMALLY,AFEWMINUTESLATERTHESPEEDISAUTOMATICALLYINCREASEDTO1000RPMANDTHEFAULTLIGHTISONANALYZETHEPROBLEMOFTHETHROTTLEPEDALLINEMEASURETHEACCELERATORPEDAL2HIGHENDWIRINGVOLTAGEIS5VOLTS,BUTTHEREISNOREVERSEJOINTBUCKLEPARKINGSTATUS,HARNESSCONNECTIONNORMALBUTAFTERSTARTINGTHEVEHICLEVEHICLEVIBRATIONLOOSEJOINTCAUSEVOLTAGEINSTABILITYAFTERFIXINGTHEJOINTWITHADHESIVETAPE,REMOVETHETROUBLEFAULTFOURLIMPINGHOMEWHATSTHEMEANINGOFLIMPINGHOMEAPATTERNOFENGINETROUBLERUNNINGHOMEECUDETECTEDAFAULTINTHEENGINEBUTNOTIMMEDIATELYSTOP,BUTWILLLIMITTHEPOWEROFTHEENGINE,SOTHATTHEENGINESPEEDCANONLYREACH1500RPM,THEDRIVERCANDRIVETOTHENEARESTREPAIRSTATIONFORMAINTENANCEITSASELFPRESERVATIONMODELSEVERALTYPESOFFAILURESFREQUENTLYENCOUNTEREDINSERVICEONTHEMARKETTHATCANCAUSELAMENESSTOANDFROMHOME41OILCIRCUITPROBLEMTHEOILCIRCUITINCLUDESLOWPRESSUREOILCIRCUITANDHIGHPRESSUREOILCIRCUITLOWPRESSUREOILINLETBLOCKINGTHEOILSHORTAGEANDTHEOILRETURNLINEISPRESSEDANDCANCAUSETHELIMPHOMEFAILUREMODETHEHIGHPRESSUREOILLEAKAGE,FLOWMEASUREMENTUNITFAULT,DAMAGE,HIGHPRESSUREOILPUMPINJECTORINTOTHEOILLEAKORINJECTORNEEDLESTUCKCANALSOCAUSEFAILURETOLIMPHOMECASESHAANXIWP10336TRACTORDURINGTHERIDE,THEFAULTYLIGHTSSUDDENLYSHONEATTHESAMETIMETHEREWILLBENOOILPHENOMENONTHESPEEDCANONLYREACH1500RPMAFTERPARKINGRESTARTNORMALAGAINRUNNINGADISTANCEANDTHESAMEFAULTINSPECTIONPROCESSAFTERINSPECTION,REPORTED“RAILPRESSUREDEVIATION“OR“EXCESSIVEFUELINJECTION“INVESTIGATIONFOUNDTHATTHEOILPIPEJOINTISFOLDED,ANDAFTERPROCESSINGTHETUBINGTROUBLESHOOTINGREMARKTHERAILPRESSUREDEVIATIONEXCEEDSTHELIMITORTHEQUANTITYOFFUELINJECTIONEXCEEDSTHELIMIT,WHICHISATYPICALMALFUNCTIONOFOILSUPPLYGENERALFAULTFORAROADRUNNINGNORMALLY,BUTUPHILLWILLSUDDENLYINCREASEINNONOILANDTHEFLASHINGCODELIGHTISONBROADANDUPHILLWILLSUDDENLYINCREASEINNONOIL,LIGHTANDFLASHCODEPARKINGISNORMALAFTERRESTARTING,BUTTHEFAULTOCCURSAGAINDURINGOPERATION