2016 Jones & Bartlett Learning SAMPLE PURPOSES ONLY

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2 BRIEF NTENTS SETIN 1 Foundation and Safty APTER 1 Why Disl? APTER 2 arrs and Employability Skills APTER 3 Workplac abits APTER 4 APTER 5 alth, Safty, and Prsonal Protction Equipmnt Basic Tools, Fastnrs, and Lifting Dvics SETIN 2 Disl Engin Fundamntals APTER 6 Basic Engin Trminology and prating Principls APTER 7 APTER 8 Disl Engin Emissions Disl Engin ombustion Systms SETIN 3 Engin onstruction and pration APTER 9 APTER 10 APTER 11 APTER 12 APTER 13 ylindr omponnts ylindr Blocks and rankshafts ylindr ads and Valv Train Mchanism Disl Engin Lubrication Systms Disl Engin ooling Systms SETIN 4 Ful and Ful Systms APTER 14 APTER 15 APTER 16 APTER 17 APTER 18 APTER 19 APTER 20 APTER 21 APTER 22 APTER 23 APTER 24 APTER 25 APTER 26 APTER 27 What Is Disl Ful? Low Prssur Ful Systms Functions of a igh Prssur Ful Systm ydraulic Nozzls Govrnors Multipl Plungr Injction Pumps Distributor Typ Injction Pumps Elctronic Signal Procssing Principls Elctronic Signal Procssing - Input ircuits Elctronic Distributor Typ Injction Pumps Elctronic Unit Injctors and Unit Pumps ummins Unit Injction Systms EUI Injction Systms ommon Rail Ful Systms

3 BRIEF NTENTS iii SETIN 5 Air Induction and Exhaust Systms APTER 28 Air Induction Systms APTER 29 Fixd Gomtry and Wastgatd Turbochargrs APTER 30 Variabl Gomtry and Sris Turbochargrs APTER 31 Disl Engin Emissions APTER 32 Exhaust Gas Rcirculation APTER 33 APTER 34 APTER 35 APTER 36 harg Air ooling Exhaust Aftr-tratmnt Systms Exhaust Systms and Engin Rtardrs D- BD Systms SETIN 6 EM Srvic Information and Engin Systms APTER 37 APTER 38 APTER 39 APTER 40 APTER 41 Navistar Dtroit Disl atrpillar Volvo - Mack PAAAR SETIN 7 Engin Elctrical and ybrid Driv Systms APTER 42 APTER 43 APTER 44 APTER 45 APTER 46 APTER 47 APTER 48 D Battry Srvicing and Tsting Advancd Battry Tchnology D Starting Systms D harging Systms Elctrical Wiring and Rpair ybrid Driv Systms and Sris Typ ybrid Drivs Allison ybrid Driv Systms

4 APTER 7 NATEF Tasks g n i n r a L LY t t N Knowldg bjctivs tl r a B ES & S s P n R o J PU 6 E 1 20 PL AM S Thr ar no NATEF Tasks for this chaptr. Aftr rading this chaptr, you will b abl to: 1. Idntify and dscrib th catgoris of noxious missions from disl ngins. (pp ) 2. Dscrib th mchanisms that form noxious missions in disl ngins. (pp ) 3. Explain common stratgis usd to rduc noxious missions from disl ngins. (pp ) 4. Dscrib missions standards for disl ngins. (pp ) 5. Idntify and dscrib th major mission monitoring and control systms usd to rduc noxious missions from disl ngins. (pp )

5 Disl Engin Emissions Skills bjctivs g n i n r a tt L LY N l t r a B ES & S s P n R o J PU 6 E 1 20 PL AM S Thr ar no Skill bjctivs for this chaptr.

6 102 SETIN II DIESEL ENGINE FUNDAMENTALS Introduction Tchnological innovations in today s disl ar drivn by missions lgislation. Ths lgal standards aim to rduc and liminat th production of noxious substancs from all intrnal combustion ngins, including dislpowrd vhicls FIGURE 7-1. Tchnological advancs mad to mt ths standards hav not sidlind disls but instad hav producd clanr ngins that ar mor fficint and powrful. Today s ngins also hav gratr driving rfinmnt and nois rduction than any prvious gnration of ngins. Emissions rduction is a crucial part of ngin tchnology. Idntifying th missions uniqu to disls, and how thos missions ar formd, nabls tchnicians to bttr undrstand ngin and mission systm opration. Emissions standards also hav implications for srvic practics and procdurs bcaus tchnicians ar rquird to maintain vhicls in complianc with missions standards. Familiarity with missions lgislation that outlins standards for ngin durability, srvic tool capabilitis, on-board communication btwn lctronic control moduls, and slf-diagnostic capabilitis of mission control systm opration is also hlpful to tchnicians. Is Disl Dirty? Th public prcption of dirty disl is not without foundation FIGURE 7-2. Emissions lgislation for disl ngins has laggd bhind lgislation for gasolin ngins. Although passngr vhicls wr quippd with missions controls bginning in th lat 1950s, th first missions standards for havy-duty disls wr not You Ar th Truck Tchnician n & ff ighway Vhicl Emissions 13% thr A 2005 truck arrivs at your shop with th complaint that th xhaust is blowing xcssiv black smok and th ngin has low powr. Th drivr has also rcivd a fin for th xcssiv missions and has an ordr to hav th vhicl s mission-rlatd dfcts rpaird. You bgin to prpar a rpair stimat by idntifying and diagnosing th possibl causs of th powr loss and black smok. n concrn you hav is whthr th ngin is too worn out to rpair and nds rbuilding. You invstigat this possibility by prforming a crankcas prssur tst according to th manufacturr s rcommndations. It turns out that th ngin dos hav xcssiv crankcas blow-by and th ngin is likly too worn to prform any rpairs that would rduc th mission- and powr-rlatd problms. 1. What parts would you rplac during an ngin ovrhaul to minimiz blow-by missions from th crankcas? 2. What othr parts would you rcommnd rplacing or tsting that may also impact th missions and powr complaints? 3. ow ar th missions-rlatd problms possibly rlatd to th rducd powr output from th ngin? 87% n & ff ighway Vhicl Emissions 58% 42% thr 1970 Air Emission Invntory 2010 Air Emission Invntory stablishd until th 1970s. n rason for lagging mission standards is that th numbr of disl ngins in us is small compard to th numbr of gasolin ngins in us. In fact, disl ngins ar usd primarily in havyduty buss and trucks and mak up approximatly 5% of th vhicl rgistrations in North Amrica. Emission standards for disl ngins bgan to bcom mor noticabl

7 APTER 7 Disl Engin Emissions 103 as missions from gasolin-fuld vhicls droppd which mad th proportion of missions producd by disls ris. Data stimats from th 1980s and 1990s show that disl contributd mor than 50% of th missions in ovrall missions invntoris a disproportionat amount whn you considr that disls ar only 5% of th vhicls on th road. Ths numbrs do not paint th whol pictur, howvr. Actual masurmnts showd that disl xhaust mad up only 24% of ovrall air missions, far lowr than stimats prdictd by EPA modls. Longr distancs ar travld by havy-duty disls; 40% of total accumulatd trip distancs ar mad by disl-powrd commrcial vhicls such as buss, havy trucks, and dlivry vhicls. Also, disl-powrd vhicls carry much havir loads than gasolin-fuld vhicls. And, sinc 2005, thr has bn a dramatic incras in th us of disl-fuld vhicls usd for transportation. For instanc, according to statistical data, in th US in 2011, 23% of th vhicls usd for transportation wr Emissions arbon Dioxid Watr xids of Nitrogn ydrocarbons arbon Dioxid Sulfur Dioxid Particulats Ful TENIIAN TIP Disl ngins built aftr 2010 ar approaching nar zro missions in ral-world masurmnts. Mor particulat is lft on th road by a truck s tirs than is mittd from its xhaust. n study of lat-modl disl ngin missions found that th numbr of particls in th air of th avrag living room is highr than in lat-modl disl xhaust. A rcnt study compltd by th Univrsity of alifornia found that mor particulat is producd by charbroiling a singl hamburgr patty than by driving a MY disl truck. Th study notd that a fully loadd 18-whlr disl-ngin truck would hav to driv 143 mils (230 km) at highway spd to produc a mass of particulat quivalnt to that producd by cooking a singl charbroild hamburgr patty. disl powrd. Whn all of ths factors ar brought togthr, th full pictur shows that disls travl much farthr, carrying havir loads, whil using lss ful. A disl-powrd vhicl will produc lowr missions than gasolin-powrd vhicls for vry ton of wight transportd pr mil. Today s disls ar in fact as clan as, if not clanr than, gasolin ngins. In fact, modrn disls mit clos to zro missions; snsitiv, rsarchgrad instrumnts ar now rquird to vn masur missions mittd from today s disl vhicls. lassification of Emissions All intrnal combustion ngins produc missions, which ar by-products of th combustion of ful FIGURE 7-3. los to 2,000 substancs ar idntifid as Air xygn 22% Nitrogn 76% thr 2% + umidity

8 104 SETIN II DIESEL ENGINE FUNDAMENTALS ngin missions. Not all of ths missions ar harmful to humans or plant lif. Emissions that ar hazardous to human or plant lif ar idntifid as noxious and classifid into four main catgoris: hydrocarbons (s), carbon monoxid (), oxids of nitrogn (N X ), and particulat mattr (PM). Ths catgoris of noxious missions ar rfrrd to as rgulatd missions bcaus lgislation limits thir production from motor vhicls and quipmnt. thr missions ar not rfrrd to as noxious, but som do fall into th catgory of grnhous gass (GG). GGs ar blivd to trap hat in th atmosphr which contributs to global warming FIGURE 7-4. arbon Dioxid An additional mission, carbon dioxid ( 2 ), has also bn garnring attntion rcntly. Until 2009, carbon dioxid ( 2 ), a by-product of normal combustion, was not a rgulatd mission bcaus it was not considrd toxic to animal or plant lif. owvr, much attntion has bn givn to its rol as a GG, so much so that public intrst in rducing th production of 2 has turnd to rgulating 2 missions. Bginning in th US in January 2009, lgislation passd imposing mandatory limits on carbon missions from all motor vhicls TABLE 7-1 and TABLE 7-2. Th Som of th infrard radiation scaps through th atmosphr, th rst is absorbd and rmittd by th grnhous gasss. This causs th lowr atmosphr and Earth's surfac to gradually hat up. Atmosphr Earth Europan Union s EUR standards hav had dirct limits on carbon dioxid sinc 2007 but only for passngr vhicls and not trucks. In North Amrica, howvr, carbon dioxid limits ar indirctly rgulatd by fulconomy standards. Bcaus carbon dioxid is a normal by-product of combusting carbon-basd fuls, rducing ful consumption will in turn lowr 2 output. ydrocarbons ydrocarbon missions ar formd from unburnd ful. Fuls ar classifid as hydrocarbons bcaus thy ar mad of mostly hydrogn and carbon atoms. ydrocarbons in th atmosphr will ract with N 2, an oxid of nitrogn, in th prsnc of sunlight to form photochmical smog, which is a form of air pollution rsmbling a hazy brown or rddish fog in th atmosphr. Exposur to hydrocarbons is also associatd with human halth problms, including cancr. arbon Monoxid arbon monoxid is a colorlss, odorlss, and tastlss gas that is poisonous in concntrations of as littl as 0.3%. arbon monoxid is cratd as a rsult of incomplt combustion of carbon-basd fuls. This gas was onc Som radiation is rflctd by th atmosphr and th arth Solar radiation passs through th atmosphr Most of th radiation is absorbd by th Earth's surfac, warming it. Infrard radiation (hat) is mittd from various sourcs

9 APTER 7 Disl Engin Emissions 105 TABLE 7-1: GG Standard for arbon Dioxid Emissions from n-ighway Disl-Powrd Vhicls atgory Yar EPA 2 Emissions (grams/ton/mil) National ighway Traffic and Safty Administration (NTSA) Gallons/1,000 mils/ton Mdium-Duty Mdium-Duty avy-duty avy-duty TABLE 7-2: 2007 GG Standard for arbon Dioxid Emissions from Vocational Applications of Disl-Powrd Vhicls atgory Light avy-duty lasss 2 5 Mdium avy-duty lasss 6 7 avy avy-duty lass 8 prvalnt in vhicl xhaust gas, in particular whn lad was usd as a ful additiv. ontrary to common blif modrn gasolin-powrd vhicls still produc carbon monoxid (vn thos using lctronically controlld combustion systms and catalytic convrtrs) and can still caus svr poisoning and vn dath if a prson is xposd to xhaust gass in confind spacs whr th xhaust gass cannot scap frly into th atmosphr. ighr comprssion prssurs and xcss air usd in disl combustion limits carbon monoxid formation in disls. Undr most conditions, ful is abl to find nough oxygn molculs to ract with, and highr comprssion prssurs push molculs mor closly togthr which incrass th liklihood of chmical ractions. xids of Nitrogn xids of nitrogn and N X ar trms for th sam catgory of missions formd from combining nitrogn with oxygn. Thr ar svral diffrnt oxids of nitrogn, which th x in N X dsignats, but two ar most commonly found in ngin missions. Th first is nitric oxid (N), a colorlss, odorlss, and tastlss gas that quickly convrts to nitrogn dioxid (N 2 ) in th prsnc of oxygn. N 2 is a rddish-brown, poisonous gas, and it is a major contributor to smog. Ths gass EPA 2 Emissions (grams/ton/mil) should not b confusd with nitrous oxid (N 2 ) also known as laughing gas which is usd as an ansthtic. Nitrous oxid is also usd to boost ngin prformanc whn dlivrd to th combustion chambr through th intak manifold. N X and Smog xids of nitrogn ar particularly harmful ngin missions for a coupl of rasons. First, N X is an ssntial ingrdint to th formation of smog. n warm days in th prsnc of sunlight, volatil organic compounds (Vs), which ar chmically ractiv molculs containing carbon, caus N X to brak down and form ground-lvl ozon ( 3 ), a noxious gas molcul. Lik N X, ozon can damag lung tissu, sting ys, irritat th nos, and aggravat rspiratory problms such as asthma and bronchitis. In addition, N X missions can also form nitric acid, contributing to acid rain. Without N X missions from th ngin, photochmical smog would simply not form. Particulat Mattr NTSA 2 Emissions Gallons/1,000 mils/ton As th nam suggsts, particulat mattr rfrs to th combination of liquids and solid particls mittd from th xhaust pip and crankcas of a disl ngin. Particulat

10 106 SETIN II DIESEL ENGINE FUNDAMENTALS mattr originating from th xhaust is obsrvd as soot particls mittd during ngin acclration FIGURE 7-5A. Black carbon mostly maks up this mission. In nwr disl-powrd vhicls, particulat missions ar almost undtctabl FIGURE 7-5B. Though lss visibl, liquids in th xhaust, such as oil droplts and sulfat compounds, ar also considrd to b particulat mattr. il droplts mak up th bulk of particulat mattr originating from th ngin crankcas. Particulat mattr is rgulatd and classifid by particl siz FIGURE 7-6. Four catgoris xist: PM-50, PM-10, PM-2.5, and ultrafin PM. PM-50, which is particulat mattr smallr than 50 microns in diamtr, is th only particulat mattr visibl to th nakd y, and it falls quickly to th ground. PM-10 is particulat mattr smallr than 10 microns in diamtr, and PM-2.5 is particulat mattr smallr than 2.5 microns in diamtr. PM-2.5 is a subst of PM-10, but it is catgorizd sparatly bcaus it is considrd mor hazardous and rquirs sparat accounting. Ultrafin, or nano, particls ar thos btwn 5 and 50 nanomtrs (nm) in diamtr. Whil ultrafin PM accounts for 50 90% of th numbr of particls in disl xhaust, it is only 1 20% of th total particulat mass. Fin particls (PM-10 or smallr) rmain airborn for days or vn months. Airborn particulat mattr has many sourcs; it is stimatd that transportation producs narly a third of total particulat mattr. Particulat mattr in th atmosphr is rsponsibl for th hazy apparanc of th sky on smoggy days. owvr, th largst proportion of xhaust, ultrafin PM and PM-2.5, is not vn visibl to th y bcaus it is microscopic. Th small siz of ths particls is what maks disl particulat hazardous. Safty Exhaust particls smallr than 10 microns ar spcially dangrous bcaus thy rmain airborn for a long tim and can pntrat into th dpst parts of th lung whn brathd in. Ths small particls within th lungs aggravat rspiratory conditions such as asthma and bronchitis. Particulat mattr is also blivd to carry othr toxic, combustion-formd compounds with it into th lungs and bloodstram. ompounds found in soot such as polycyclic aromatic hydrocarbons (PAs) ar carcinognic; in fact, disl soot itslf is classifid by many govrnmnt agncis as ithr a probabl or known cancr-causing agnt. According to rports by th alifornia Air Rsourcs Board (ARB) disl soot has bn rsponsibl for a significantly high lvl of risk of cancr causd by air pollution. Sulfats Whn disl ful is rfind from ptrolum oil that is pumpd from th ground, varying quantitis of sulfur naturally combin with oil. Burning sulfur containd in ful producs sulfat (S X ) missions, which can contribut to air pollution and acid rain. Th biggst hazard of burning ful containing sulfur is that it racts with othr combustion by-products to incras th formation of particulat mattr. Formation of Emissions Undrstanding whr and how missions ar formd provids hlpful insight into th dsign and opration of various ngin systms and stratgis that manufacturrs A B

11 APTER 7 Disl Engin Emissions 107 Ultrafin PM 0.1 microns Ultrafin PM 0.1 microns PM microns PM microns PM microns hav dvlopd to rduc and liminat missions from disl ngins. Manufacturrs attmpt to ithr prvnt th formation of missions by altring combustion conditions that lad to th production of missions, or clan up missions aftr thy ar producd. rankcas controls and xhaust aftrtratmnt systms ar xampls of systms usd to prvnt noxious missions from ntring th atmosphr aftr thy ar formd. Most othr ngin and ful systm tchnologis ar dsignd to targt incylindr formation of missions. Emission Sourcs uman air Width 60 microns Disl vhicls produc missions from two sourcs: th xhaust systm and th crankcas. Rgulatory attntion until rcntly has bn givn only to xhaust missions. N N N Prfct ombustion Ignition Sourc Nitrogn xygn ydrocarbon Watr at Rlativ Particl Sizs Thr ar no rgulations for vaporativ missions from disls bcaus ngligibl missions ar producd from th vaporation of disl ful. rankcas missions from disls wr rgulatd bginning undr EUR 5 and EPA 07 mission standards, about 40 yars aftr similar rgulations bgan for gasolin ngins. This dlay in rgulations was bcaus missions from this ara of th ngin ar diffrnt and hav a smallr nvironmntal impact compard to gasolin ngins. Exhaust Emissions PM microns Exhaust missions, also occasionally rfrrd to as tailpip missions, consist of wast combustion gass FIGURE 7-7. Watr, carbon dioxid, and nitrogn mak up th bulk of th xhaust contnt, but harmful carbon monoxid, N Nitrogn Dioxid Noxious Emissions S S Particulat arbon Monoxid

12 108 SETIN II DIESEL ENGINE FUNDAMENTALS hydrocarbons, oxids of nitrogn, and particulats accompany th rlativly harmlss substancs. Noxious missions from disl xhaust mak up % of all combustion by-products. In comparison, untratd missions from spark-ignition ngins burning gasolin compris 1 3%. Exhaust missions ar formd during th combustion procss. Injctor spray charactristics hav a major influnc on combustion quality, which in turn influncs th typs and quantitis of missions producd FIGURE 7-8. Disl-ngin xhaust missions ar uniqu du to th highr combustion tmpraturs and prssurs producd through turbocharging and high comprssion ratios. Disl ful proprtis and th natur of comprssion ignition opration also chang th typ of missions formd and th procsss forming thm. Piston Ring Blow-by Road Draft Tub g n i n r a tt L LY N l t r a B ES & S s P n R o J PU 6 E 1 20 PL AM S rankcas Emissions rankcas missions ar mainly composd of cylindr blow-by gas and oil droplts FIGURE 7-9.Blow-by is th lakag of air past th piston rings into th crankcas. In any ngin, blow-by occurs mostly during th comprssion strok. This happns bcaus th piston rings cannot form a prfct gas-tight sal, which prmits som air to lak past th rings. In disls, only air is prsnt in th cylindr during th comprssion strok. This mans most Ful Injction Spray Formation primary brakup Vaporization rankcas il Mixtur Formation scondary brakup Ignition Air Turbulnc ombustion and Emission Formation Nx Particulat Mattr Unburnt 's ombustion Efficincy

13 APTER 7 Disl Engin Emissions blow-by consists of air. During th powr strok whn cylindr prssur is highst, littl blow-by taks plac bcaus th comprssion rings ar tightly sald. Almost no blow-by taks plac during th xhaust and intak stroks. Whil som blow-by is normal, th volum of blow-by will incras as cylindr walls and piston rings war FIGURE In fact, masuring crankcas prssur to valuat th volum of blow-by is on of th bst masurmnts of ngin war. Engins with xcssivly high crankcas prssur typically hav a poor piston ringto-cylindr wall sal, which in turn incrass blow-by. Unlss vntd to th atmosphr, blow-by gass built up in th crankcas would caus sals and gaskts to lak oil from th ngin. Blow-by only bcoms a problm whn it travls through th crankcas to th atmosphr and picks up droplts of oil thrown from th crankshaft and piston cooling jts. Blow-by containing liquid oil droplts is catgorizd as a particulat mission. Until 2006, disl ngins could vnt crankcas blow-by dirctly to th atmosphr FIGURE 7-11A. Today, disls ar quippd with crankcas controls FIGURE 7-11B. rankcas controls ar covrd in mor dtail latr in th book. 109 A g n i n r a tt L LY N l t r a B ES & S s P n R o J PU 6 E 1 20 PL AM S ydrocarbon Production ydrocarbon missions ar composd of unburnd ful and ar producd from th vaporation of ful or from incomplt combustion. Disl ngins produc comparativly littl hydrocarbon missions in contrast to gasolin-fuld ngins. With almost no vaporativ ful vapors, hydrocarbon missions du to ful vaporation ar drastically lowr from disls than from gasolinfuld vhicls. Disl cold-start missions ar also ngligibl in comparison to gasolin ngins. Excss air and B FIGURE 7-11 A. An opn crankcas vntilation systm usd by a 3126B atrpillar ngin. B. This ummins sris ngin uss a crankcas vntilation systm that sparats oil from air using a coalscing filtr locatd insid th housing ovr th valv covr. highr combustion tmpraturs and prssurs nsur mor complt combustion of ful in a disl. Evaporativ Emissions Ful vaporation, such as from a ful tank, can b a major sourc of hydrocarbon missions from gasolin vhicls. owvr, disl ful vaporizs at a highr tmpratur than gasolin. Disl ful s low volatility mans littl vaporation of ful taks plac from disl ful tanks FIGURE Whn disl ful dos vaporat, it xrts vry littl prssur in comparison to gasolin. For ths rasons, thr is no rquirmnt for vaporativ missions controls on disl ngins. Disl ful dos not asily vaporiz. This tndncy can b asily obsrvd at ful-pump islands whr spilld ful lingrs for days and wks bfor disapparing. Lightr, mor volatil fractions of th ful vaporat mor quickly. avir, mor viscous ful molculs lingr on pumps and concrt surfacs longr than spilld gasolin molculs do.

14 110 SETIN II DIESEL ENGINE FUNDAMENTALS Day Masurmnt of Evaporativ Emissions 1.0 SED Tst - Grams/Tst Fdral Standard Gasolin Disl Estimat Incomplt ombustion Incomplt combustion is rsponsibl for th majority of hydrocarbon missions from disls. Th most common causs for incomplt combustion ar: Inadquat combustion tim Improprly mixd air and ful oars spray droplts Insufficint combustion hat and prssur Ful can also somtims avoid combustion in crtain aras around th combustion chambr. n major ara whr hydrocarbons and carbon monoxid form is abov th top comprssion ring btwn th piston crown and th cylindr wall in an ara calld th crvic volum FIGURE Manufacturrs rsarch has discovrd that clos to 50% of hydrocarbon missions from disls originat from ful trappd in this rgion. This rgion prvnts propr hating and mixing of ful with air. Th gap btwn th cylindr had gaskt, block dck, and cylindr had is anothr rgion contributing to hydrocarbon missions. In today s disls, manufacturrs hav movd th top comprssion ring closr to th piston crown, and mad othr modifications to piston dsign, to minimiz crvic volum. Th fir ring of th had gaskt has also bn movd closr to th cylindr in modrn ngins. Difficult-to-burn ful molculs calld aromatic molculs caus a charactristic smll from disl xhaust at idl and low spd. Ths molculs ar complx hydrocarbons which ar unusually shapd and somtims not compltly combustd, spcially during low spd and load conditions whn cylindr prssur and tmpraturs ar rducd FIGURE Disl ful aromatic contnt is limitd by lgislation to rduc hydrocarbon missions and carbon monoxid production. TENIIAN TIP xidation catalysts hlp rduc and liminat disl xhaust smll. Damagd, missing, or cold catalytic convrtrs ar common causs for th strong odor from xhaust and ful with high aromatic contnt. arbon Monoxid Production arbon monoxid is formd whn ful has only partially ractd with oxygn. With adquat hat, prssur, and combustion tim, carbon monoxid would chang into carbon dioxid. Low combustion tmpraturs and prssur, lack of oxygn, or insufficint burn tim typically contribut to incrasd carbon monoxid production from an ngin.

15 APTER 7 Disl Engin Emissions 111 Disl ngins produc only vry small amounts of carbon monoxid compard to gasolin-fuld ngins. Unlik gasolin-fuld ngins, disl-fuld ngins do not oprat nar stoichiomtric air-ful ratios. Gnrally, disl combustion uss xcss air, which mans a gratr liklihood of complt ractions btwn ful and oxygn; this limits carbon monoxid production. igh comprssion ratios and turbocharging, which incras combustion prssur and push molculs closr togthr in th disl combustion chambr, also nabl gratr liklihood of chmical ractions btwn oxygn and ful. xids of Nitrogn Production Nitrogn is a rlativly inrt gas and has many industrial applications whr that proprty is usful (.g., shock absorbrs, wlding shilding gas, A lak dtction). In ngins, howvr, high combustion tmpraturs and prssurs vntually caus ractions btwn nitrogn and oxygn FIGURE Bcaus nitrogn maks Aromatic ydrocarbon A N onvntional ydrocarbon B N N Tmpratur up 78% of air, its shr volum mans a grat potntial xists to ntr combustion ractions. Evn though disl ngins produc rlativly low lvls of s and missions, disl ngins hav a natural capability to produc far mor N X than gasolin-fuld ngins. ombustion tmpraturs abov 2,500 F (1370 ) contribut to N X formation. Bcaus disl ful burns at clos to 4,000 F (2200 ), incrass in tmpraturs abov 2,500 F (1370 ) ar asily achivd. ombustion tmpratur incrass abov 2,500 F (1370 ) also caus N X production to incras xponntially. Th thr main rasons that disl ngins produc highr lvls of N X ar thir highr comprssion ratios, cylindr prssurs, and tmpraturs which acclrat th spd of chmical ractions. Particulat Mattr Production Particulat mattr is formd in th disl combustion chambr from th tiny drops of ful sprayd into th chambr nar th nd of th comprssion strok. It s important to rmmbr that ths ar liquids and not vapors. Vapors not liquids burn. Tim and hat ar ndd to convrt disl ful into vapor. Th low volatility of disl ful promots poor vaporization, but vaporization is ndd for complt combustion. In disl combustion thr is a limitd amount of tim for vaporization to tak plac bcaus ful is injctd nar th nd of th comprssion strok. Bcaus disl ful vaporization is poor, liquid ful burns from th outsid in FIGURE Burning ful from th outsid in, with limitd tim, hat, and air, will produc a small carbon nuclus; this is th primary componnt of particulat. Disl ful chmistry also contributs to particulat formation. arbon, rathr than hydrogn, tnds to b N N N3 N4 N6 Nx xygn Nitrogn Prssur Nitric xid Nitrogn Dioxid

16 112 SETIN II DIESEL ENGINE FUNDAMENTALS Ful Vapor at xygn Rich Rgion xygn Bakd - Not Burnt Ful ydrogn All Gon utsid to Insid Burn xygn Dpltd Zon Magnifid arbon Particl lft ovr aftr combustion bcaus it racts mor slowly with oxygn du to th gratr numbr of bonds in a carbon atom. Four bonds ar formd by carbon atoms in comparison to a singl bond formd by hydrogn. Th carbon-to-carbon bonds ar spcially strong and difficult to brak. Whn carbon-to-carbon bonds ar unbrokn, black carbon will agglomrat, or chain togthr, to form black sooty particulat. Th short amount of tim to injct, vaporiz, distribut, mix, and burn th ful at th nd of disl s comprssion strok mans particulat mattr production is highr from a disl ngin than in a gasolin ngin. Gasolin will vaporiz and mix with air quickly during th intak and comprssion stroks, which also prmits mor tim for improvd mixtur prparation. A common stratgy to rduc particulat formation is to mak ful droplts smallr by using finr atomization. This is don by using highr prssurization of ful through an injctor with smallr, mor numrous spray hols. Particulat mattr production can also b rducd by using highr combustion prssurs and tmpraturs to acclrat th burn rat, which causs mor complt oxidation of th carbon contnt of disl ful. Sulfat Production Whn disl ful is rfind from ptrolum that is pumpd from th ground (minral ptrolum), varying quantitis of sulfur naturally combin with th oil. Whn sulfur burns in th combustion chambr, sulfat (S X ) missions ar formd. Sinc th mid-1990s, in North Amrica and around th world, sulfur contnt has bn progrssivly rducd to minimiz S X production. In 2007, sulfur contnt in North Amrica droppd from a high of 500 parts pr million (ppm) to a low of 15 ppm. This chang followd th us of ultra-low-sulfur ful usd for many yars in Europ. Furthr rductions ar schduld for No xhaust mission standard currntly xists for sulfur compounds alon. Instad, sulfur contnt in ful is limitd. Rgulating sulfur contnt out of ful nabls th us of sophisticatd xhaust missions aftrtratmnt systms such as particulat filtrs, slctiv catalyst rduction, and N X adsorbrs. igh ful-sulfur contnt dstroys th ability of ths dvics to convrt noxious missions into othr harmlss combustion by products FIGURE Particulat Emissions and Engin Spd Maximum ngin spd is part of th missions information on disl ngins. Tachomtrs in disl-powrd vhicls hav a lowr maximum ngin spd limit than gasolin-fuld ngins. Disl ngins cannot turn as fast as gasolin ngins bcaus thy will not compltly burn ful at high spd. Th pr-combustion procsss Sulfur S Watr? Unknown

17 APTER 7 Disl Engin Emissions of atomizing, distributing, vaporizing, and mixing ful with air in th fw dgrs of ngin rotation nar th nd of th comprssion strok rquirs tim. If an ngin s piston is rotatd too fast through th cylindrs top dad cntr (TD), not nough tim is availabl to proprly complt th pr-combustion mixtur prparation stags. In that situation, th ngin simply runs out of tim to proprly prpar and burn th ful air mixtur. If th maximum ngin spd limits ar xcdd, disl ngins will produc xcssiv noxious xhaust missions FIGURE This is why disl mission dcals hav a maximum ratd spd and th ful systm govrnor must limit top ngin spd. TENIIAN TIP Th maximum ngin spd listd on th mission dcal is part of th rgulatory mission crtification for an ngin family. Tchnicians ar rquird to nsur that ngin spds cannot b xcdd through any ful systm malfunction, tampring, srvic practics, or procdurs. arbon Dioxid Production Exhaust Smok Dnsity As with all xhaust missions that can damag th atmosphr and th nvironmnt, carbon dioxid is bst known as a grnhous gas. Intrnationally, lgislation rquirs vhicl manufacturrs to limit 2 missions from thir vhicls. arbon dioxid is a normal byproduct of combustion of carbon-basd fuls. Disl ngins offr a good solution to mt both ful milag standards and rduc ovrall 2 missions. Typically, 2 missions from disls ar 30 40% lowr than an quivalntly powrd gasolin-fuld ngin. Factoring in th us of biodisl, a 100%-rnwabl ful sourc, th nvironmntal footprint of th disl ngin can b vn smallr. Emissions Standards Around th world, concrns about th ngativ nvironmntal and halth impacts of vhicl missions hav producd lgislatd standards for noxious missions. Th Europan Union (EU) and th Unitd Stats hav dvlopd two mission standards adoptd by most othr countris in th world. Th gratst numbr of countris us mission lgislation mad law by th Europan Parliamnt which was phasd in btwn 1993 and In th EU, thr ar six progrssiv stags for rducing missions bginning with EUR 1 until th most currnt EUR 6 from In th US, th Environmntal Protction Agncy (EPA) has dvlopd mission standards. Th US and anada us US EPA standards. hina has dvlopd its own standards that closly approximat EUR standards. Japan follows Japans Ministry of Land, Infrastructur and Transportation (JMLIT) standards FIGURE Both EPA and EUR standards rgulat narly th sam noxious missions; th only diffrnc is th classification of hydrocarbons into svral diffrnt subcatgoris. GG missions, which ar vhicl missions blivd to contribut to global warming, ar a rcnt EPA Dns Black Visibl 3,000 RPM 2,000 RPM 1,000 RPM Prcntag of Maximum Engin Load 100 EPA EUR EUR or EPA Japan

18 114 SETIN II DIESEL ENGINE FUNDAMENTALS rgulation. Th EPA has st ful conomy standards for havy-duty vhicls to rduc carbon dioxid missions, a major GG gas, whil th EUR standard currntly limits carbon dioxid only in light-duty vhicls. Whil both standards vary in th rgulation of light-, mdium-, and havy-duty vhicls, th EPA and EUR mission standards for off-road ngins ar harmonizd with idntical standards applying to ngins usd in havy quipmnt, mining, locomotivs, and othr no-road vhicl applications. Emission limits and tsting procdurs ar th significant diffrncs btwn EUR and EPA standards. For havy-duty ngins, EUR and EPA missions ar masurd on a dynamomtr, which runs th ngin only through a prcis squnc of changing spd and load conditions to simulat driving in urban and on-highway conditions. avy-duty missions ar masurd in grams pr horspowr pr hour, whil light-duty missions ar masurd in grams pr mil or kilomtr. Engin tsting only, rathr than tsting th ntir vhicl, is ncssary bcaus a havy-duty ngin may go into a wid varity of chassis, such as a truck or bus. A mor comprhnsiv and rigorous tst procdur prformd by th EPA masurs missions undr a widr varity of oprating conditions with slightly lowr maximum mission thrshold than th EUR standards. Somtims, within an individual country, multipl missions standards ar in forc. For xampl, two sts of missions standards ar usd in th Unitd Stats a fdral standard and a stat standard (alifornia). Fdral standards ar st by th EPA; alifornia standards ar st by th alifornia Air Rsourcs Board (ARB). alifornia standards ar strictr than fdral standards; this is du in part to high population dnsity and gographical factors that contribut to poor air quality in alifornia. alifornia is th only US stat prmittd by fdral law to nact vhicl missions standards strictr than thos st by th fdral govrnmnt. thr stats can choos to adopt alifornia s standards, but only alifornia can b th first to surpass standards st by th fdral govrnmnt. Th following sctions will dtail th dvlopmnt of North Amrican missions standards, applid to disl vhicls sold thr (such as missions dcals and usful lif rquirmnts), and spcializd standards for diffrnt typs of disl-fuld vhicls. Standards Dvlopmnt Emissions standards for disl-fuld vhicls ar constantly volving with mission rductions rquird by ach nw standard, causing th dvlopmnt of nw tchnology to rduc missions. Th first missions standards for disls wr not stablishd until Ths first standards limitd pak smok opacity for havy-duty disls. A disl missions standard for oxids of nitrogn followd in 1984, and a particulat mattr standard was first stablishd in In 1993, a nw standard rquird that disl ful s typical 5 7% sulfur contnt b rducd to lss than 1%. Rducing ful s sulfur contnt hlpd rduc particulats and minimiz corrosion and dposit formation in ful systm componnts. Maximum aromatic contnt was limitd simultanously in Europan manufacturrs rducd sulfur contnt much arlir and introducd slctiv catalytic rduction (SR) systms. SR allowd optimization of ngin powr output whil rducing particulat missions clos to North Amrican standards without a ful pnalty. Bcaus sulfur contnt in fuls can poison th most rcnt convrtr substrats, ultra-low-sulfur ful was introducd for th 2007 mission systms; this droppd sulfur contnt. Europan manufacturrs rducd sulfur contnt much arlir and introducd slctiv catalyst rduction (SR) systms, an xhaust aftrtratmnt systm for rmoving N X missions, bfor using particulat filtrs. SR allowd optimization of ngin powr output whil rducing particulat missions to lvls clos to North Amrican standards without th ful pnalty in this markt which is snsitiv to highr ful prics. Minimizing th production of missions producd in th cylindrs, rathr than xhaust-basd rduction, was th traditional control stratgy until Until that point, th problm of disl xhaust s rlativly cool tmpraturs and air-rich output prvntd th us of convntional catalytic convrtr tchnology, which is usd in automobils. owvr, whn disl particulat filtrs (DPFs), anothr xhaust aftrtratmnt systm dsignd to filtr soot particls from th xhaust, wr introducd for all on-highway havy-duty disls, xhaust-basd rduction bcam a major stratgy for rducing disl missions. Until 2009, carbon dioxid ( 2 ), a by-product of normal combustion, was not a rgulatd mission bcaus it is was not considrd toxic to animal or plant lif. owvr, bcaus of its rol as a GG, public intrst in rducing th production of 2 has turnd to rgulating 2 missions. Rathr than rgulat 2 standards dirctly, which th EUR standard dos only on lightduty vhicls, ful conomy standards ar stablishd to indirctly limit 2 production. Th rasoning is that with rducd ful consumption, lss 2 is producd. Ful conomy standards targting 2 for ar th most rcntly schduld mission standards. For tractor-trailr combinations, vhicl missions standards for targt 7 20% rduction in 2 missions ovr th 2010 baslins. Vocational vhicls, havy-duty

19 APTER 7 Disl Engin Emissions EPA Standards for Nw Trucks and Buss Nitrogn xid missions * Particulat Mattr missions * 115 pickup trucks, and vans must achiv at last a 10% rduction in 2. To mt th 90% rduction in NX output for 2010, svral SRs wr introducd FIGURE Th most common SR systms on havy-duty trucks and buss is liquid SR. This systm uss a ura molcul dissolvd in watr to brak down NX. A fw light- and mdiumduty vhicls manufactur ura molculs in a uniquly dsignd catalyst Emissions Dcals n way that countris nsur complianc to missions standards is by issuing dcals. For xampl, vhicls and quipmnt sold for on- or off-highway us in North Amrica must hav an missions dcal affixd to th vhicl or ngin FIGURE Th dcal contains missions information indicating to what standard th vhicl or ngin is crtifid. Th dcal also includs important information for th tchnician about part rplacmnt and adjustmnt procdurs, softwar calibration fils, and othr rlvant data that could affct missions production. For xampl, on a disl ngin, th dcal will contain information about valv lash sttings, injction timing, ful rats, and th prsnc of missions systm g n i n r a tt L LY N l t r a B ES & S s P n R o J PU 6 E 1 20 PL AM S * EPA's mission standards for trucks and buss ar basd on th amount of pollutionmittd pr unit of nrgy (xprssd in grams pr brak horspowr hour). A B

20 116 SETIN II DIESEL ENGINE FUNDAMENTALS componnts. Bcaus havy-duty ngins ar crtifid for missions output in grams pr horspowr-hour, dcals ar affixd to th ngin. Ths ngins ar usd in a varity of chassis configurations, so masuring missions for distanc travld is impractical. Light-duty vhicl missions ar crtifid by vhicl typ, and missions ar masurd in mass units for vry mil or kilomtr travld. Emissions dcals for light-duty vhicls ar placd on th chassis in th vicinity of th ngin compartmnt. Usful Lif Rquirmnt Starting in 2004, disl ngins must mt missions standards ovr what is trmd th usful lif of th ngin. Th dfinition of usful lif dpnds on th typ of ngin. In 2004, usful lif was dfind as: Light-Duty: 110,000 mils (177,000 km) or 10 yars Mdium-Duty: 185,000 mils (297,728 km) or 10 yars avy-duty: 435,000 mils (700,065 km) or 10 yars Usful lif now includs not only rgulatd missions, but 2 as wll, so ngins must b built mor durably to mt ths standards. Adaptiv stratgis must b usd to compnsat for dtrioration factors which could push an ngin out of complianc. avy-duty Standards Emissions milstons for havy-duty disls wr updatd bginning in 1991 through to 1994; thy wr also updatd in 1998, 2002, 2007, and This sris of updats ld to dramatic drops in missions, with particulat missions dropping 90% from 2004 to 2007 and both N X and particulat dropping 90% from 2007 to 2010 FIGURE For xampl, ngin manufacturr diagnostics (EMD) apply to all MY2007 and nwr havy-duty ngins usd in vhicls ovr 14,000- lb gross vhicl wight rating (GVWR). Also starting in MY2007, crankcas mission controls wr rquird. n turbochargd ngins, th crankcas could b vntd to th atmosphr, but th wight of crankcas missions was totald with xhaust missions. owvr, crankcas controls ar mor practical for havy-duty disls bcaus dtrioration of crankcas missions with ngin war was addd to th xhaust dtrioration factors. Emission standards for 2010, EPA 10, havy-duty disls wr: Particulat mattr: 0.01 g/bhp-hr xids of nitrogn: 0.20 g/bhp-hr Non Mthan ydrocarbon (NM): 0.14 g/ bhp-hr Particulat (g/hp/hr) D Standard Nx (g/hp/hr) avy-duty on-board diagnostics (D-BD) ar part of th nwst mission lgislation and us a mor sophisticatd st of mission standards that wr introducd in A phas-in priod from on ngin family from a manufacturr to all ngin familis was rquird by D-BD standards ar dvlopd continuously by th Socity of Automotiv Enginrs (SAE) and adoptd on a yarly basis by th EPA as a lgislatd standard. Th D-BD systm is dsignd to dtct potntial conditions which could lad to xcssiv missions FIGURE 7-23.

21 APTER 7 Disl Engin Emissions 117 ff-road Standards Standards for off-road quipmnt ar diffrnt than thos for on-highway quipmnt FIGURE Ths standards ar rfrrd to as Tir 1, 2, 3, and 4 mission standards and ar harmonizd worldwid with Europan standards. Tir 1, stablishd in 1994 and phasd in btwn 1996 and 2000, rprsnts th arlist phas in incrasingly strictr mission limits, with Tir 4 bing th final, clanst, standard of th four phass. Ths standards ar basd on horspowr ratings, with largr horspowr ngins taking longr to implmnt missions standards. ff-road disls hav mission standards applid dpnding on th powr and yar th ngin is producd. Emission standards lag on-highway ngins but approach th sam lvls by th phas-in priod. Tir 1 standards rmaind in ffct until th Tir 2 and/or Tir 3 standards took ffct. Tir 2 and Tir 3 standards wr stablishd in 1998 to b phasd-in for various horspowr ratings btwn 2001 and An intrim Tir 4 standards phas-in bgan in 2011, and a final standard bgan bing implmntd in Emission standards for off-road quipmnt lag on-highway ngins but will vntually approach th sam lvls FIGURE U.S. EPA n-ighway Standards >33,000 lb. GVWR 19,500 to 33,000 lb. GVWR 8500 to <19,500 lb. GVWR* Light Duty** US '04 Tir 2 (phas-in ) US '07 US '10 * Not: avy duty vhicls btwn ,000 lb. GVW hav th option of crtifying ngin or doing a whol crtification using a chassis dynamomtr (starting 2008). *Not: Mdium duty passngr vhicls in th ,000 lb. GVW ar includd in th Tir 2 arrangmnts. U.S. EPA ff-ighway Standards hp 100 to 175 hp 75 to 100 hp <75 hp Tir 1 / Stag I Tir 3 Tir 2 Tir 2 Tir 2 Tir Tir 2 / Stag II Tir 3 Tir Tir 3 / Stag IIIA Tir 4 Tir 4 Tir 4 EPA and EU non-road mission rgulations: hp ( kw) Intrim Tir 4 / Stag IIIB Final Tir 4 / Stag IV hp (37 56 kw) hp (57 74 kw) hp ( kw) hp ( kw)

22 118 SETIN II DIESEL ENGINE FUNDAMENTALS Tsting Emissions EUR and EPA mission standards masur mission outputs rcordd whn a dynamomtr is placd on ithr an ngin or chassis FIGURE hassis dynamomtrs masur missions basd on distanc travlld by th complt vhicl. Bfor a vhicl or ngin can b crtifid for us on or off highway, th tst protocol, which is a prcis schdul of varying spd and load conditions, must b compltd to dtrmin whthr th vhicl or ngin missions rmain blow th maximum limits through th tst cycl. Th mass of missions producd by th ngin or vhicl is collctd and masurd during th driving cycl. pacity Tsting pacity tsting is th common masurmnt for valuating smok dnsity from disl ngins. This is basd on th principl of light xtinction by xhaust smok. A bam of light of a particular wavlngth is passd through a sampl of smok FIGURE pacity, th masur of smok dnsity, is basd on th prcntag of light blockd. Th darkr th smok, th highr th prcntag of opacity. A masur of 75% opacity mans 75% of th light is blockd, whil 25% is transmittd. Th procdur usd by law nforcmnt agncis to masur smok missions is basd on th SAE J1667 Snap Acclration Tst. This is a non-moving vhicl tst which can b conductd along th roadsid, in a truck stop, Engin Dyno at a vhicl rpair facility, or at inspction maintnanc tst facilitis. Th Snap Acclration Tst is intndd to b usd on havy-duty trucks and buss powrd by PM 2 N X Gas tmpratur oolr ollcting bag Prssur monitor Air filtr for ambint air Frsh air blowr (for gas sampling) Main blowr

23 APTER 7 Disl Engin Emissions 119 disl ngins. Th procdur is intndd to provid an indication of th stat of maintnanc and/or tampring of th ngin and ful systm rlativ to th factors that affct xhaust smok. Emission ontrol and Monitoring Systms Emissions standards rquir that manufacturrs monitor and control disl ngin missions. Whil crtain monitoring systms ar rquird for disl ngins, manufacturrs ar rlativly fr to dtrmin how thy will control missions to mt standards, as long as thy do mt th standards. Thy dsign systms and procsss that will ffctivly and cost-fficintly mt th standards. This sction will dtail svral common mission monitoring and control systms. Disl Engin Emission ontrols Disl missions can b controlld in a varity of ways. ommon missions controls will b discussd in dtail in othr chaptrs in this volum. Som xampls of ngin tchnology rquird to mt th Engin Manufacturrs Diagnostics or EPA-07 standards includ: ommon rail injction with injction rat shaping Unit injction with injction rat shaping capabilitis Low- and high-prssur coold xhaust gas rcirculation (EGR) Variabl gomtry turbochargrs (VGT s) harg air cooling (A) Two-way oxidation convrtrs (Ds) Disl particulat filtrs (PTx Particulat Trap xidizing onvrtr) Slctiv catalyst rduction (SR) N X traps and N X adsorbrs Exhaust gas snsors wid rang oxygn and N X Disl Engin Emission Monitors Major ngin systms which influnc th production of missions ar monitord by th EMD or D-BD systms. Ths monitors ar ssntially diagnostic stratgis usd to dtrmin if an mission systm is functioning corrctly. As dtaild arlir, EMD, a pr D-BD mission monitoring systm, and D-BD ar usd on havy-duty disls. Engin Manufacturr Diagnostics EMD systms ar rquird in all MY2007 and nwr havy-duty ngins usd in vhicls ovr 14,000-lb GVWR. EMD systms chck th functioning of th ful dlivry systm, xhaust gas rcirculation systm, particulat filtr, and missions-rlatd circuit continuity and rationality for th ngin control modul (EM) inputs and outputs. To dtct mission systm malfunctions, th diagnostic managr, a pic of softwar installd in th EM, chcks to dtct any condition which could potntially caus missions to xcd maximum thrshold limits. Major mission monitors in EMD systms ar listd in TABLE 7-3. A diagnostic data link connctor locatd blow th dash and to th lft of th string column has six or nin pins and is usd to accss SAE fault cods from TABLE 7-3: Engin Manufacturr Diagnostics Engin Systm Ful systm Misfir monitoring EGR systm Boost-prssur control systms Glow plugs Disl xhaust aftrtratmnt systms (Monitor rquirs potntial faults to b dtctd bfor missions xcd standards for any of th following systms) Systm Analysis Ful prssur Ful-injction quantity Multipl ful-injction vnt prformanc Ful-injction timing Exhaust gas snsor monitoring (N X and 2 only) Must dtct misfir occurring continuously in on or mor cylindrs during idl. EGR flow rat EGR rspons rat EGR cooling systm Mass air flow rat Undr- and ovr-boost malfunctions Wastgat opration Slow turbochargr rspons harg air coolr fficincy n-tim Glow plugs nabld Intak hatr opration xidation catalyst Lan N X catalyst SR catalyst N X trap PM trap

24 120 SETIN II DIESEL ENGINE FUNDAMENTALS on-highway trucks and buss. Th fastst and most modrn communication protocol btwn srvic tools and vhicl ntworks is J Data is transmittd in both dirctions btwn th vhicl and srvic tool using a nin-pin data link connctor. mission-rlatd fault xcds a thrshold lvl, th MIL is rquird to switch on to alrt th drivr of a potntial fault FIGURE Mor about D-BD systm opration is found in othr chaptrs in this volum. D-BD monitors includ th faturs listd in TABLE 7-4. avy-duty n-board Diagnostics omprhnsiv omponnt Monitoring (M) Th M is part of th D-BD systm. Its function is to monitor lctrical circuits oprating powrtrain componnts that: D-BD missions standards for havy-duty dislfuld ngins bgan in D-BD has many spcific standards govrning vrything from th styl, typ, and location of lctrical and diagnostic connctions, to communication standards, missions thrsholds, fault cod structur and mission monitoring stratgis. Th malfunction indicator lamp (MIL) joind othr lamps on th instrumnt panls of havy-duty vhicls to mt D-BD rquirmnts FIGURE 7-28.Whnvr an an caus a masurabl missions incras during any rasonabl driving conditions Ar usd for othr BD monitors Ar rquird to monitor input componnts for circuit and rationality faults Ar rquird to monitor output componnts for functional faults g n i n r a tt L LY N l t r a B ES & S s P n R o J PU 6 E 1 20 PL AM S Th M is not tid to mission thrsholds. Any lctrical problm rlatd to mission systms will caus th MIL to illuminat. FIGURE 7-28 Th MIL, a rquirmnt undr D-BD, switchs on to alrt th drivr of a potntial fault.

25 APTER 7 Disl Engin Emissions 121 TABLE 7-4: n-board Diagnostics (BD) Engin Systm NM atalyst convrsion monitors N X convrting catalyst monitoring Misfir monitor Ful systm monitor Exhaust gas snsor monitor EGR systm monitor Systm Analysis Disl oxidation catalyst Disl oxidation catalyst fficincy monitor DPF rgnration assistanc monitor Disl oxidation catalyst SR assistanc monitor Slctiv catalyst rduction catalyst Efficincy monitor Slctiv catalyst rduction fdback ontrol monitors Slctiv catalyst rduction tank lvl Similar in function to EMD but dos not st th MIL Ful rail prssur snsor circuit Ful rail prssur snsor rang Injctor cod missing or invalid Ful systm injction prssur control Ful rail prssur monitors Injction timing Injction quantity Zro ful calibration Fdback controls Air-ful ratio snsors: tailpip N X 2 snsor control modul EGR rat systm monitor EGR coolr/egr coolr bypass monitor EGR systm slow rspons EGR closd-loop control limits monitor Mass airflow closd-loop control limits monitor Engin Systm Boost-prssur control systm monitor Particulat filtr monitor rankcas vntilation prssur old start and warmup monitoring Glow plug rsistanc monitor omprhnsiv componnt monitor (M) Systm Analysis Intrusiv turbo position and rspons monitoring Intrusiv wastgat monitoring Functional ovrboost monitoring Functional undrboost monitoring Thrshold undrboost monitoring harg air coolr monitoring DPF filtr fficincy and missing substrat monitors DPF frqunt rgnration monitor DPF incomplt rgnration monitor DPF fdback control monitors DPF rstriction monitor rankcas prssur is monitord but faults do not st th MIL. Glow plugs nabld Glow plug rsistanc Intak hatr opration All circuit monitoring for componnts supporting othr monitors and powrtrain control opration ar th sam as EMD.