楊四軍武科大教授單元十 汽車檢測與維修(課件)-《汽車專用英語 第三版》同步教學 （人交版）

汽車商標汽車及其歷史汽車發(fā)動機汽車底盤單元一單元二單元三單元四汽車電氣設(shè)備汽車車身汽車使用說明書及維修手冊汽車檢測與維修設(shè)備單元五單元六單元七單元八汽車維護汽車檢測與維修新能源汽車概述汽車商務(wù)接待單元九單元十單元十一單元十二

單元十

活塞連桿組故障診斷與修復汽車檢測與維修

學習目標

完成本學習任務(wù)后，你應(yīng)該能：1.了解汽車診斷與維修的基本流程；2.掌握汽車診斷與維修術(shù)語的英語表達；3.對相關(guān)內(nèi)容進行閱讀和翻譯；4.填寫故障分析檢查表；5.正確完成課后練習。建議學時4

學時Text

Despitethebestmaintenance,problemsmayoccurwithyourcar,thenyourcarneedsservice.Ifyouseea“checkengine”ora“serviceenginesoon”lightinyourcombinationmeter,yourcarhasstoredadiagnostictroublecode,whichmeansthecomputersystemonyourvehiclehasdetectedaproblemwithinvarioussystemsitcontrols.Howtoproceedwithtroubleshooting?Automobile'sdiagnosticsandrepairprocedures(Fig.10-1)areasfollowing.AutomotiveDiagnosisandMaintenanceFig.10-1AutomobilesDiagnosticsandRepairProceduresText

CustomerProblemAnalysisCheckTakethecombinationmeterforexampletoshowthecustomerproblemanalysischecksheet(Tab.10-1)asfollowing.AutomotiveDiagnosisandMaintenanceText

ProblemSymptomConfirmationandCircuitInspectionAcarhasmanydifferentsensorsthatmonitorthevariousvehiclesystems.Ifthetroublecodelighthasbeenilluminated,itshowsthevehicleentersinto“l(fā)impmode”.Take“enginetrouble”asanexample,whenyouseea“malfunctionindicatorlight”(Fig.10-2)ora“serviceenginesoon”lightinyourcombinationmeter,Itmeansyourcarhasstoredadiagnostictroublecode.AutomotiveDiagnosisandMaintenanceFig.10-2MalfunctionIndicatorlightText

ProblemSymptomConfirmationandCircuitInspectionLocateyourvehicle'sdiagnosticconnector(Fig.10-3),mostlyitisinthedriverseatattheside.Ifnot,pleasecheckyourowner'smanual.AutomotiveDiagnosisandMaintenanceFig.10-3DiagnosticConnectorText

ProblemSymptomConfirmationandCircuitInspectionConnectcodereadertotheconnector.Thecodereaderwillautomaticallyturnonandpromptyouthenextoperationonreadingfaultcode(Fig.10-4).Oncethetroublecodehasbeenidentified,itsidentificationwillbedisplayedonthecodereader.AutomotiveDiagnosisandMaintenanceFig.10-4ReadingFaultCodeText

ProblemSymptomConfirmationandCircuitInspectionUponcompletingtherepairwork,it'snecessarytoclearthetroublecodeandrechecksystem.Aftercodeshavebeenclearedthecomputersystemisreadyforinternaltesting,thismeansthatwhilethecarisinoperationthecomputerisperformingtests.Thesetestsarecalled“monitors”,mostcarshavebetween4and8monitorsystems.AutomotiveDiagnosisandMaintenanceText

RepairorReplaceWhenthetroublesarefound,carneed“RepairorReplace”.Thismeanstorepairorchangethedefectiveparts.Nowtake“changesparkplugs”forinstance,explainingthe“RepairorReplace”operation.Parkthecaronaflatdrysurface,engineoff,pulluptheemergencybrakeset.Gatherthepropertools:Socketwrench,sparkplugsocket,gappingtool,safetyeyewear,glovesandtowelsetc.AutomotiveDiagnosisandMaintenanceText

RepairorReplaceFirst,identifytheignitionsystemyourcarhas,mostcarshaveaDIS(directignitionsystem).Gentlybutfirmlytwisttheboottoloosentheseal,nowremovethesparkplugwire(Fig.10-5).Thengentlypullthesparkplugwirefromthesparkplug.Removetheplugwirefromthecoilterminal.AutomotiveDiagnosisandMaintenanceFig.10-5RemovingtheSparkPlugWireText

RepairorReplaceRemoveallplugwiresfromthepackaging,straightenthemoutandorganizetheplugwiresfromthelongesttotheshortest.Paysattention,plugwiresindifferentcylinderwillbedissimilarwiththeaimoflatermatchingandreplacingplugwires(Fig.10-6)atatime.AutomotiveDiagnosisandMaintenanceFig.10-6MatchingandReplacingPlugWiresText

RepairorReplaceNext,removedebrisfromthesparkplughole,thenuseasocketwrenchandsparkplugsockettoloosenandremovesparkplug(Fig.10-7)bycounterclockwise.Inspectsparkplug'sworkanddamagestate.AutomotiveDiagnosisandMaintenanceFig.10-7RemovingSparkPlugText

RepairorReplaceBeforereinstallingnewsparkplugs,trytomakesurewhetheryouareinstallingismatchedforyourcarandenginesizeornot.Measuringthesparkpluggap(Fig.10-8)betweentheelectrodeswithafeelergauge,mostsparkpluggapsarebetween0.035～0.045inch.Anincorrectsparkpluggapwillresultinlowpower,poormileageandpossiblyacheckenginelightnotice.AutomotiveDiagnosisandMaintenanceFig.10-8MeasuringtheSparkPlugGapText

RepairorReplaceSavetheoldsparkpluginthenewsparkplugboxes,storethemforfuturereference.Onceyouhavecompletedthesparkplugchange,remembertostarttheengineandinspecttherunningcondition,itshouldbesmoothwithnoextranoises.Ifyourengineisrunningrough,trytocheckthesparkplugwirestomakesurenoneofthempoppedofforloosened.AutomotiveDiagnosisandMaintenance參考譯文

盡管車輛維護的很好，故障仍然不可避免的會出現(xiàn)。出現(xiàn)故障時，車輛就需要維修作業(yè)。如果你看到儀表盤上的故障指示燈或發(fā)動機維護燈亮著，這就表明你的車存儲了一個故障碼，也就意味著汽車電腦在車輛的各種系統(tǒng)中檢測到了某個故障。如何檢修車輛故障呢？汽車診斷與維修的基本流程如圖10-1所示。汽車診斷與維修圖10-1診斷維修基本流程圖參考譯文

客戶描述故障分析下面以組合儀表為例說明客戶描述故障分析表（表10-1）。汽車診斷與維修參考譯文

故障癥狀確認和系統(tǒng)檢查汽車上裝配有許多不同的傳感器用以監(jiān)測車輛各個系統(tǒng)的工作狀況。如果故障指示燈亮了，就意味著車輛進入“保護模式”。以發(fā)動機故障為例，當你看到儀表盤上的故障指示燈點亮(圖10-2)或發(fā)動機維護燈亮著，這就表明你的車存儲了一個故障碼。汽車診斷與維修圖10-2故障指示燈點亮參考譯文

故障癥狀確認和系統(tǒng)檢查找到車輛的故障診斷接口（圖10-3），大多數(shù)是在駕駛員座位一側(cè)，如果不在，請查閱用戶手冊。汽車診斷與維修圖10-3故障診斷接口參考譯文

故障癥狀確認和系統(tǒng)檢查將解碼器接上診斷接口，解碼器會自動啟動并提示你進行故障碼讀?。▓D10-4）的下一步操作。一旦故障碼被確定，解碼器就會將確定的故障碼顯示出來。汽車診斷與維修圖10-4讀取故障碼參考譯文

故障癥狀確認和系統(tǒng)檢查每次維修作業(yè)完成后，必須清除故障碼并再次確認系統(tǒng)。一旦故障碼被清除，車輛電腦就進入自我測試狀態(tài)，這也就意味著當車輛起動時計算機自動執(zhí)行內(nèi)部系統(tǒng)測試。這種測試也被稱作“監(jiān)測”，大多數(shù)車輛有4～8個監(jiān)測系統(tǒng)。

維修與更換故障部位被確定后，接下來就是維修或更換車輛故障零件或系統(tǒng)。下面以“更換火花塞”為例講解“維修和更換”作業(yè)。將車輛停在水平干燥的地面上，關(guān)閉發(fā)動機，拉起駐車制動器。準備工具：套筒扳手、火花塞套筒、厚薄規(guī)、安全眼鏡、手套和毛巾等。汽車診斷與維修參考譯文

維修與更換首先，確認車輛點火系統(tǒng)的類型，大多數(shù)汽車的點火系統(tǒng)為DIS（直接點火）型。輕輕晃動火花塞膠套使其松曠。拆卸高壓線（圖10-5）與火花塞及分電器的連接。汽車診斷與維修圖10-5拆卸高壓線參考譯文

維修與更換從維修包中取出所有新的高壓線，按最長到最短的順序弄直和整理高壓線。注意：不同汽缸的高壓線長度不一樣，這便于稍后匹配更換高壓線（圖10-6）。汽車診斷與維修圖10-6匹配更換高壓線參考譯文

維修與更換接下來，用壓縮空氣清除火花塞孔，然后用套筒扳手和火花塞套筒按逆時針方向預松并拆卸火花塞（圖10-7）。檢查火花塞的工作和損壞情況。汽車診斷與維修圖10-7拆卸火花塞參考譯文

維修與更換在安裝新的火花塞之前，確定準備安裝的火花塞是否與發(fā)動機尺寸相匹配。并用厚薄規(guī)（又稱塞尺）測量火花塞電極間隙（圖10-8），大多數(shù)車輛的火花塞間隙為0.035～0.045英寸。采用劣質(zhì)火花塞將會導致發(fā)動機功率下降、油耗上升，甚至會導致發(fā)動機故障指示燈點亮。將換下的火花塞保存在新的火花塞盒內(nèi)，以備以后作參考之用。更換火花塞后記得檢查發(fā)動機工作情況：發(fā)動機應(yīng)運轉(zhuǎn)流暢、無異響。如果發(fā)動機工作不穩(wěn)定，則檢查各缸高壓線有無脫落或松動現(xiàn)象。汽車診斷與維修圖10-8火花塞間隙測量ReadingMaterial

EngineoverheatingTherearemanyconditionsoftheautomobilethatresultinoverheating,andthedegreeofoverheatingisindicatedbythetemperaturegaugeontheinstrumentpanel.Someconditionswillcauseonlyaslightchangeintherecordedtemperature,otherswillresultinarapidriseintemperatureandviolentboilingofthecoolant.Stillsomemaycauseonlyaslightincreaseinrecordedtemperature,butwillbemorenoticeableinengineperformance.EngineTroubleshootingReadingMaterial

EngineoverheatingWhentroubleshootingthecauseforoverheatingandconsequentlossofcoolant,thefirststepistomakecarefulvisualinspectiontoseeifthereisanyevidenceofexternallinkage.Allsurfacesoftheradiatoranditshoseconnectionsshouldbecarefullyinspected.Leaksgenerallycausecorrosion,whichiseasilyseen,Thevisualinspectionalsomustincludethecoolingfananditsdrivebelt.Itisnottoounusualforcrackstoformintheenginewaterjacket.Whencracksoccur,theconditionisusuallyindicatedbyextremeoverheating.Thecrackisoftendifficulttolocate,becauseitisnotalwaysvisibletothenakedeye.Theconditionisalsocomplicatedbythefactthatthecrackusuallywillclosewhentheengineiscold,andopenonlywhentheengineisatoperatingtemperature.EngineTroubleshootingReadingMaterial

CleaningtheCoolingSystemUnlessveryseverelycloggedwithrustandhardscale,coolingsystemscanbecleanedwithspecialchemicalsdesignedforthepurpose.Theprocedureistofillthesystemwithwater,thenputinthechemical.Thechemical,afterdissolvingtherustandscale,isflushedfromthesystem.Inseverecasesofcloggedradiators,itisnecessarytoremovethemandhavethemcleanedbyspecializedequipment.EngineTroubleshootingReadingMaterial

HighonConsumptionQuiteoftenhighoilconsumptionisblamedonthepistonrings.Whilewornpistonringsandcylinderwallsdocauseincreasedoilconsumption,thereareagreatnumberofotherthingsthatcouldbeatfault,eithersinglyorincombination.Wornvalveguidesarealsoafrequentcauseofhighoilconsumption.Whenoilisbeingconsumedbypassingthroughtheengine,itusuallywillcauseheavybluesmoketocomefromtheexhaust,particularlyaftertheenginehasidledforseveralminutes.EngineTroubleshootingReadingMaterial

LowoilPressureInmostcasesoflowoilpressure,thepressureissatisfactorywhentheengineisfirststartedup,thenitdropsastheenginewarmsup.Thisconditionisalmostpositiveproofthatexcessiveclearanceexistsatsomepoint,orpoints,suchasconnectingrodbearings,mainbearings,camshaftbearings,etc.Whencold,theoilhasthickenedanddoesnotflowasreadilythroughtheclearance.Whentheoilheatsupandthinsout,itflowsthroughthewornbearingsofastthatthepumpcannotmaintainsufficientpressure.EngineTroubleshootingReadingMaterial

AbnormalEngineNoisesandTheirCausesThefollowinglistingwillpointoutthemostcommoncausesofsounditselfandwhatmustbedonetoeliminatethem.1.Pistonslapisaverycommonnoisemostnoticeablewhenanengineiscold.Apistonthatslapsagainstthecylinderwallproducesahollow,muffled,bell-likesound,quiteaudiblewhenanengineisoperatingunderloadatlowrpm.Pistonslapresultsfromwornpistonsorcylinders,collapsedpistonskirts,excessivepiston-to-cylinderwallclearance,misalignedconnectingrods,oralackoflubricatingoil.Therefore,inordertocorrectpistonslap,itwillbenecessarytoreplacedorresizethepistons,reborethecylinderorreplacethesleeves,replaceorrealigntherods,oraddoiltotheengine.EngineTroubleshootingReadingMaterial

AbnormalEngineNoisesandTheirCauses2.Anabnormalsoundoriginatingfromsomeformofpiston-ringproblemisaudibleduringengineacceleration.Tocorrectthecauseofringnoise,itmaybenecessary,therefore,toreplacetherings,thepistons,orthesleevesorreborethecylinders.3.Asoundnotfrequentlyheardinanengineisthatofapistonringstrikingtheringridgeatthetopofthecylinder.Thisparticularproblemcausesaverydistinctandhigh-pitched,metallicrappingorclickingnoiseaudibleatallenginespeedsbutparticularlyondeceleration.Torepairthecauseofthissound,itwillbenecessarytoreplacethepistonpinorconnectingrodbearings.EngineTroubleshooting參考譯文