377 Vorsprung durch Technik Training精通维修下载 -litre V8 FSI engineSelf-Study Programme 377All rights reserved. Technical specifications subject to change without AGI/@ +49-841/89-36367AUDI AGD-85045 IngolstadtTechnical status: 03/06Printed in
精通维修下载
Special features of the current Audi vee engine family are the 90-degree included angle between the cylinder banks and the spacing of 90 mm between the cylinders. The first member of the family was the -litre V6 FSI engine. The -litre V8 FSI engine is also a member of this family. It is available in two versions - a comfort-oriented basic version (used for the first time in the Audi Q7) and a sporty high-revving version for the new RS4. A V10 engine with litres of displacement will also be available. Like the RS4 engine, the V8 in the Q7 has FSI direct injection, which – following five victories in the Audi R8 Le Mans racing car – is now being introduced in a production eight-cylinder model. The V8 was retuned for use in the Audi Q7. A fuller torque curve up to nominal speed and spontaneous response – these are the characteristics of this new engine. The engine excels not only with its dominant power output and high maximum torque. The resultant driving performance is excellent, even in the face of tough competition.精通RS4 high-revving engine维修下载 _045
Table of contentsIntroduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Engine mechanicalsCranktrain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Crankcase ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Chain drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Drive, ancillary units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16精通维Oil circulation system修下Design . . . . . . . . . . . . . 载. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 Oil pump and oil filter module. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19htOil pan Audi RS4t. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20p:Oil circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21// system in Audi Q7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22omCooling system in Audi RS4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23Air circulation systemAir intake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Intake manifold flaps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Vacuum hoses in the Audi RS4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Vacuum hoses in the Audi Q7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Fuel systemFuel system in the Audi Q7/RS4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Exhaust systemExhaust system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Exhaust flap control in the Audi RS4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Secondary air system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34精通Engine management维修下System overview, Audi Q7 (Bosch MED ) . . . . . . . . . . . . . . . . . . . . . . . . . . . .36载System overview, Audi RS4 (Bosch MED ). . . . . . . . . . . . . . . . . . . . . . . . . . . . .38 hOperating modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41 ttpCAN data bus interfaces (powertrain CAN data bus) in the Audi Q7. . . . . . . . .42:/CAN data bus interfaces (powertrain CAN data bus) in the Audi RS4 . . . . . . .43/wwStart mode of the Audi RS4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . mode of the Audi RS4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . self-study programme teaches the basics of the design and function of new models, new automotive components or new self-study programme is not a Repair Manual!All values given are intended as a guideline only and refer to the software version valid at the time of publication of the SSP. For maintenance and repair work, always refer to the current technical literature.
IntroductionThe -litre V8 FSI engine is supplied in the new The following main objectives were set for Audi Q7, Audi A6, Audi A8 and in the development of the Q7 engine: – High specific engine power: 257 kW/350 bhp out of litres (15 bhp more than MPI engines)– High torque: 440 Nm out of litres– Reduction of fuel consumption by approx. 5 % (~360 g/kWh at 2000 rpm and 2 bar)– Short and compact design– Modular engine concept based on V6 FSI engine for V8 and V10 FSI (synergy)– High idling quality– High standard of comfort with regard to acoustics and running qualityNote– Low engine weight– Off-road capability of Audi Q7 engine The technical descriptions of this engine refer mainly to the V8 basic engine in the Audi Q7 and the high-revving engine in the Audi RS4.精通维修Q7 engine下载 _0036
Technical features The main technical differences between the base engine and the high-revving engine lie in the – Petrol direct injectionfollowing modules:– Homogeneous-charge mode – Roller cam followers with hydraulic backlash – Cranktraincompensation – Timing gear– Flywheel-side chain drives for camshafts and – Cylinder headancillary units – Oil supply– Variable camshaft adjustment for intake and – Engine coolingexhaust camshafts – Intake path– Two-stage magnesium variable inlet manifold– Exhaust systemwith integrated tumble flap (not fitted in RS4)– Engine management– Drive-by-wire throttle control – for compliance with exhaust emission standardsFor an exact description of the differences, please EU IV/LEV IIrefer to the relevant section.精通维修RS4 engine下载 _0027
IntroductionTorque/power curve320460Max. torque in Nm280420V8 FSI basic engine in Q7380240V8 FSI high-revving engine in RS4Nm200300Max. power output in kW160V8 FSI basic engine in Q7V8 FSI high-revving engine in RS4kW80精通02000500070009000维Engine speed in RPM修下载 hSpecificationsttp:Q7RS4//Engine codeBARBNSwwwType of engineV8 90° vee angle 4V in cm4163weMax. power output in kW (bhp)257 (350) at 6800 rpm309 (420) at 7800 . torque in Nm440 at ~3500 rpm430 at 5500 rpmcoNumber of valves per cylinder4 mBore in in ratio~ : 1Firing order1–5–4–8–6–3–7–2Engine weight in kgapprox. 198*approx. 212**Engine management Bosch MED Bosch 2x MED grade98 / 95 RONExhaust emission standardEU IV/LEV II*with automatic transmission**manual gearbox including clutch and dual-mass flywheel8
Engine mechanicalsCranktrainCylinder block The cylinder crankcase has a closed-deck design. *Aluminium alloys are classed as hypoeutectic or The closed-deck design is stronger than the open-hypereutectic, depending on their silicon content. deck design. "Alusil" has a hypereutectic silicon content of 16 to In an open-deck cylinder block, the water jacket for 18 % so that primary silicon is precicipated on cooling the cylinders is open at the top. solidification of the molten metal. The cylinder crankcase is made of a low-pressure gravity diecast aluminium-silicon alloy, is A multistage honing process is applied. The silicon hypereutectic* and has a silicon content of 17 % grains in the cylinderbores in the form of micro-(AlSi17Cu4Mg). scopically small, very hard particles are stripped to The cylinder crankcase underwent special heat give the necessary wear resistance of the cylinder treatment in order to increase its strength. surfaces for the piston and piston rings. The cylinder liners are mechanically stripped. – Cylinder spacing: 90 mm The cylinder crankcase of the high-revving engine – Cylinder bank offset: mm was machined to higher specifications due to the – Overall engine length: 464 mm higher stresses in this component. To minimise – Cylinder block height: 228 mm warping of the cylinder manifolds, the crankcase is 精honed under stress. For this purpose, a honing 通template is attached to the crankcase before the honing proces维s in order to simulate the warping of the bolted cylinder manifold.修下载 crankcasecomPress-fitted main bearing377_006Cylinder crankcase bottom sectionThe cylinder crankcase lower section (bedplate The main bearing is symmetrically to the centre of bearing cross-member) is made of aluminium with the main bearing attached by four bolts. press-fitted iron main bearing covers made of grade The bedplate type design provides high stability. 50 nodular cast iron. It is centred using centring The bedplate has the same stabilising effect as a pins, sealed with liquid sealant and bolted to the ladder crankcase. 9
Engine mechanicalsModifications to high-revving engineCrankshaftThe crankshaft runs on five bearings and is made of At the very high engine speeds, axial vibration high-alloy tempering steel (42CrMoS4). It is 90° occurs due to the unbalance in the single-mass cranked and has no conrod journal offset. damper. This can cause the crankshaft to avoid this vibration, a dual-mass damper without The vibration damper is a vulcanised single-mass unbalance is employed in the high-revving engine. damper with unbalance. To compensate for unwanted engine vibration, heavy metal inserts are integrated in the first and – Main bearing: Ø 65 mmeighth crank webs by way of unbalance.– Main bearing width: mm– Big-end bearing: Ø 54 mm– Big-end bearing width: mm精通维修下载Cranktrain in the RS4 _035Heavy metal inserts10
Con-rodCracked con-rods made of 36MnVS4 are used in the basic engine while the conventionally split con-rods in the RS4 engine are made of 34CrNiMo8 for addition, the geometry of the con-rods was reduced for the high-revving engine and the toler-ances were reduced.– Bearing journals:Ø 54 mm – Bearing bushings: mm thick, mm wide – Length of bushing:Ø 20 mm rolled – Con-rod length:154 mm精通维修377_058下载Cracking htBreaking surfaceDuring the cracking process, the con-rod is split at a ppredetermined breaking point using a special tool.:The resultant unique breaking surface ensures the //high joining precision of the two mating _062gzweixPredetermined .breaking pointcomPistonFor strength reasons forged pistons with a slightly higher weight than conventional pistons is engines have the same piston geometry.– Piston weight without rings: approx. 290 g – Piston pin: Ø 20 mm x Ø mm x 40 mm 377_05711
Engine mechanicalsCrankcase ventilationThe crankcase is ventilated through both cylinder After the blow-by gas has passed through the fine heads. oil separator, the gas flows into the intake manifold The valve hoods incorporate a large settling space. downstream of the throttle valve. This space acts as a gravity-type oil separator. This inlet point is integrated in the coolant circula-A fine oil separator is connected to the valve hoods tion system and heated. This prevents the crankcase by means of plastic from freezing control piston, a bypass valve, a two-stage pressure limiting valve and an oil drain valve are integrated in the oil separator after start of productionIn both engines, the separated oil flows into the crankcase through the cover in the inner vee adjacent the crankcase breather (no longer through the chain housing).In the Q7 engine the crankcase is vented 精through a single chamber, . via bank 2 通only. Better antiicing protection is achieved 维in this way.修下载 hBreather pipeBreather pipeHeaterttp:Crankcase breather system//_009Non-return valve(crankcase breather)Bypass valvePressure limiting valveFine oil separator12
Function of fine oil separator Blow-by gas volume is dependent on engine load The separated oil is collected in an oil reservoir and RPM. The fine oil ("oil spray") is separated by beneath the cyclones. The oil cannot drain out of means of a cyclone separator. Cyclone separators the reservoir until the oil drain valve is opened. only have a high separation efficiency over a small The oil drain valve is closed as long as the pressure volumetric range. For this reason, one, two or three in the crankcase, . below the valves, is higher cyclones of the fine oil separator operate in parallel than in the oil separator. The valve opens auto-depending on the gas flow due to gravity only at very low engine RPM or when the engine is at a standstill, because the The cyclones are released by the control piston. pressure conditions above and below the valve are The displacement of the control piston against its in force is dependent on the gas flow rate. Piston ring flutter at very high engine RPM and low The crankcase ventilation system also includes the engine load can result in a very high gas flow rate. crankcase breather. Air is extracted downstream of the air filter and flows through a non-return valve The crankcase internal pressure is set by the two-into the crankcase from above. stage pressure control valve. The non-return valve is located at the end of the The bypass valve together with the control piston vent line and is bolted between the two cylinder ensures that the cyclones operate at the optimum banks in the engine block. operating point (if the volumetric flow rate is too A damping chamber is located below the non-return high or too low, this will impair the functioning of valve in the engine block. This prevents non-return 精the cyclones). valve flutter and eliminates noise.通When the bypass valve opens, a fraction of the A restrictor bore connects this chamber to the 维blow-by gas flows to the engine untreated, but the inner chamber of the crankcase. It has the task of remainder is optimally treated by the only a defined volume of fresh air to the 修crankcase. 下载 reservoirTriple cyclones377_011Oil drain valve13
Engine mechanicalsChain driveIllustration shows the Q7 engineChain drive A精通Chain drive BChain drive C维修下载 http://w377_012wChain drive timing gear concept is identical in all Audi vee-Q7ixengine series..The chain drive runs on two camshafts in the basic engine arce driven oby 3/8“ simplex roller chains. mPlane 1Due to their acoustic advantages, the chains were Basic drive A: developed to meet the high comfort idler gears to camshafts from crankshaftIn this case the idler gears have 40 and 24 teeth. Plane 2The camshaft sprockets have 30 drive B and C: drives camshafts from idler gearsChain drive D: drives ancillary units drive module from crankshaftHigh-revving engineCorrect chain tension is ensured by spring hydraulic 3/8“ simplex sleeve-type chains are used here. tensioners. The chain drive is maintenance-free and Their advantage is their reduced wear and higher designed for lifetime resistance at high engine two engine types differ in terms of the type of chains used and the reduction ratios in drives A, B In this case the idler gears have 38 and 19 teeth. and C. The load on the roller chains was reduced in The camshaft sprockets have 25 basic engine version by selecting a higher number of teeth. 14
Ancillary units driveThe oil pump, water pump, power steering pump and the compressor are driven by chain drive chain is driven directly by the crankshaft, deflected by an idler gear and drives the chain sprocket seated on the gear module. Air conditioner compressor精通维修Chain drive D下载 httpCoolant pump://_013Oil pumpGear modulePower steering pump15
Engine mechanicalsCylinder headDifferent features of the high-revving engineThe cylinder heads are based technically on the well-known Audi four-valve FSI cylinder heads. To match the higher engine power output and RPM, the following cylinder head components were Specificationsmodified:– Aluminium cylinder head– Intake ports are charge optimised (based on larger cross-sections)– FSI intake ports with horizontal divisions to produce a tumble effect– Intake valves are chrome-plated hollow stem valves (for weight reduction)– Four-valve technology with centralised layout of the spark plugs– Valve springs are made of a material with higher tensile strength and also have higher spring – Inlet valve: chrome-plated solid stem valveforce– Exhaust valve: chrome-plated sodium-filled – To meet the higher fuel requirements the hollow stem valve injectors are designed for higher flow rates.– Valve lift 11 mm精– Roller cam followers are more robustly designed, with peened rollers for higher strength– Light通weight, low-friction valve gear, valve actution via roller cam followers with hydraulic back-维– Camshafts have different timings and larger lash compensation, single valve spring修opening lengths– Two assembled camsh下afts per cylinder head, – Intake valve opening angle 230 crank angle driven by hydraulic swivel motors载degrees – Intake valve opening angle 200 crank angle h– Exhaust valve opening angle 220 crank angle degreesttdegreesp– Exhaust valve opening angle 210 crank angle :/– The clearance compensation elements were degrees/adopted from the VR6 engine. They have a larger wwball stroke which, in the course of testing, – Adjustment range of the camshafts is 42 crank wproved advantageous for the high-revving angle (with regard to the inflation of the zhydraulic valve clearance compensation – The adjusters are locked by locking bolts when weelement).the engine is at a standstill; Intake in advance iposition, exhaust in retard position x.– The cylinder head has a modified water jacket cwhich circulates coolant to the area between – Return spring in exhaust adjusteromthe intake port and the injector and thereby reduces the temperatures in the cylinder head – Implementation of "internal exhaust gas combustion chamber " through the use of a corresponding valve overlap– Due to modified camshaft drive reduction ratio, the camshaft adjuster has 25 teeth for chain drive, as against 30 teeth in the basic
Crankcase breatherValve hoodHall sensor精通维修下High-pressure fuel pump with fuel metering valve载 ht377_015tp:// adjusterweiAssembled adjuster with return spring377_08017
Oil circulation systemDesignThe oil supply in the basic engine, and likewise in The baffle plate is designed such that it not only the high-revving engine, is based on a classic wet prevents the crankshaft churning the oil in the sump concept. sump, but also strengthens the main bearing walls. The focal point of development was on significant In the basic engine the oil is cooled by an oil-water reduction of the oil flow rate. As a result, the oil heat in the sump for longer and is better able to the more highly stressed high-revving engine, an additional oil-air heat exchanger is used to mini-The oil flow rate of 50 litres per minute (at 7000 rpm mise the oil temperature even at high engine load. and 120 °C oil temperature) is very low for an eight-This additional heat exchanger is operated in cylinder engine. This has helped to minimise oil parallel with the heat exchanger via a thermostat. pump drive power and thus improve fuel bank 1Cylinder bank 2Oil filter moduleChain tensioner精通维修下载Hydraulic camshaft adjustment cooler (coolant)comOil pressure regulatorOil pump(gear)ThermostatFeatures exclusive to the Audi RS4377_028Oil cooler (air)18
Oil pumpThe oil pump is situated above the oil pan. The oil is drawn in through the filter in the bottom of the sump and simultaneously through the engine return duct while driving. All engine lubrication points are swept from the pressurised oil line from the engine Pressurised oil side精通维Bottom filter 修on intake side下载377_039 http:/Oil filter module/wwThe oil filter module is designed as a full-flow filter. For easy maintenance, it is accommodated in the inner of the engine. The filter element can be easily replaced without the need for special tooling. It is made of ga polymer-based nonwoven capPolymer-based nonwoven filter elementfrom the pressure side of the oil pumpto the engine circuit377_04019
Oil circulation systemSump in the Audi RS4Especially in a sports car, a reliable supply of oil in all driving situations is vitally important. The oil supply system in the high-revving engine was designed for racing applications in which it is subjected to lateral acceleration of up to g. To ensure this, the sump in the RS4 has an Aadditional system of flaps whose axis of rotation is parallel to the longitudinal axis of vehicle are arranged inside a housing. Each of the flaps opens towards the inside of the intake end of the oil the vehicle is cornering the oil flows inside the sump towards the outside of the corner. The two Direction of travel精flaps facing the outside of the corner close and hold the oil in the sump intake.通At the same time, the two flaps facing the inside of 377_037维the corner open to allow additional oil to flow into 修the intake. This ensures a sufficient supply of oil to the oil pump.下载 view Ato outside of corner xacting centrifugal _038Flap closesFlap opens(oil back pressure is increased)(oil flows into intermediate chamber)20
Oil circulation system 精通维修下载 _059Pressurised oil downstream of filterPressurised oil upstream of filter21
Cooling systemCooling system in the Audi Q7Heater heat exchangerExpansion tankCoolant temperature sender精通维Coolant pump修下载Alternator httpOil coolerThermostat:// cooling system in the new V8 engines was A map-controlled coolant thermostat is used in the oconfigured as a longitudinal-flow cooling system. basic engine. mThe cooling water flows in on the outlet side and When operating at full throttle the coolant tempera-through the cylinder head gasket into the cylinder ture is reduced to 90 °C via an electrically heated head, where it flows out longitudinally through the thermostat to avoiding increasing the tendency of chain housing cover. the engine to knock. When operating at part throttle Cooling of the cylinder webs was improved by - which is not critical with regard to knock - the drilling coolant ducts with optimised cross-sec-coolant temperature is increased to 105 °C. tional area into the webs. The thermodynamic advantages and the reduced Forced flow through these bores is ensured by friction result in a fuel saving of approx. % when means of specially sealed water ducts. operating at low part high-revving engine also has two vee-shaped Radiator fan controlforced-flow bores between the inlet valves because they are subjected to higher stresses due to the The engine control unit J623 activates radiator fan high power density. control unit J293 and radiator fan control unit 2 J672 by generating a separate PWM radiator fan control units then energise the radiator fans based on the engine control unit signal by means of a PWM radiator fan is activated by the engine control unit based on a characteristic
Cooling system in the Audi RS4Coolantrun-on pump V51精通Non-return valve维修下Coolant thermostat for additional cooler载 cooler, rightAdditional cooler, pump and thermostatomNo map-controlled coolant thermostat is used in the high-revving engine. To achieve more effective cooling, two additional coolers are used. Coolant flows continuouslythrough one of the additional coolers. The second additional cooler is opened via a cool-ant avoid excessive heating-up after shutting off the hot engine, the coolant run-on pump is activated a preset period of time after the engine is shut off. The pump run-on time and the need for additional activation of both radiator fans are determined on the basis of characteristic maps. Various measured quantities are included in the calculation (engine temperature, ambient temperature, engine oil Coolant pumptemperature and fuel consumption).377_034Thermostat23
Air circulation systemAir intakeThe intake path of the Q7 is double-chambered and Intake manifold path change-over is map-control-discharges into a variable inlet manifold made of led. The adjustment is made by the variable inlet gravity die cast aluminium. A Bosch throttle valve manifold motor V183. No feedback is given on the module with a diameter of 82 mm is located position of the variable inlet manifold. upstream of the variable inlet manifold. If the intake manifold shutoff is not functioning, The variable inlet manifold is of the two-stage type. exhaust gasquality is not impaired. In this case, the In the lower RPM range, the long intake manifold driver will notice a loss of power. path is activated in order to increase torque. In the upper RPM range, the short intake manifold path is activated. This positionproduces an increase in engine power system in the Audi Q7Throttle valve moduleVariable inlet manifoldHot-film air mass meter (HFM5)精通Hot-film air mass meter (HFM5)维修下载 manifold flapscomIntake manifold flapsAs with the variable inlet manifold, the intake mani-In the basic engine in the Q7 the intake manifold fold flaps in both engine variants are controlled flaps are activated via an electrical actuator. according to a characteristic map. In both engines For each cylinder bank, the position of the intake the intake manifold flaps are activated in the lower manifold flaps is monitored by a Hall sensor. engine load and RPM ranges. In the high-revving engine, the intake manifold flaps They are brought into abutment with the port baffles are activated by a single vacuum actuator per in the cylinder head and thereby seal the lower part cylinder bank. In this case, too, the flap position is of the intake port. The aspirated air mass now flows indicated by means of Hall the upper section of the intake port and induces a tumbling charging motion inside the cylinder. When not activated, the intake manifold flaps are open and sender and maximises the cross-sectional area of the port. All flaps in a cylinder bank are attached to a common
The intake system of the RS4 engine was designed The power flap is opened and closed by a vacuum with emphasis on maximum flow control. Pressure actuator which is map-controlled by the engine loss is minimised by a large cross-sectional areas in control unit via the variable intake manifold change-the hot-film air mass meter (HFM) and air intake over valve N335. pipe in combination with a 90 mm diameter throttle sand cast aluminium intake manifold was designed specially to match the sporty characteris-To ensure a sufficient supply of air to the engine at tic of the engine. In contrast to the basic engine, high RPM, the power flap in the air filter is opened maximum torque is produced at higher engine RPM. at engine speeds higher than 5000 RPM and at road At this engine speed, the intake manifold change-speeds higher than 200 kph. over valve would be switched to the short path for higher power output.精Intake sys通tem in the Audi RS4维Air intake修Hot-film air mass meter (HFM5)下Throttle valve module载Air intake pipe htIntake manifoldtp://Cylinder flapomAir intakeAir intakeVacuum unitfor power flapThe RS4 engine does not have a variable inlet manifold flaps377_02225
Air circulation systemVacuum hoses in the Audi RS4The conventional method of supplying vacuum to This means that connecting a vacuum line down-the brake servo and the engine components is stream of the throttle valve would offer little pros-problematic in the case of FSI of success because, in many engine operating situations, the wide open throttle valve would result in low mass flow rates and vacuum in the intake manifold housing flapAir filterSecondary air pumpVacuum unit for combination valveVariable intake manifold Activated charcoal canister change-over valve N335solenoid valve 1 N80精Activated charcoal canister通维修下载Hot-film air mass meterhtSuction jet pump t(entrainment pump)pwith integrated non-:return valve//Intake manifold flapwair flow control valve units for xintake manifold airinlet valve N112Non-return valveVacuum pump for brakes V192Vacuum reservoirBrake servoNon-return valve with Brake servo brake servo pressure relay J569sensor G29426
For this reason, in both engine versions, the requi-In this case, the vacuum produced by the suction jet site vacuum is produced by a suction jet pump and, pump is not enough to sufficiently evacuate the if necessary, additionally by an electrical vacuum brake servo. The brake servo pressure sensor G294 connected to the line to the brake servo and transmits its values to the engine control unit. The suction jet pump is connected in parallel with In the engine control unit (map controlled), the the throttle valve part upstream and downstream of brake servo relay J569 and the vacuum pump for the throttle valve. The branched air flow drives the brakes V192 are activated until requisite vacuum is suction jet pump. An extreme case is that of cold . For example, when the catalytic converter is heating up, the throttle valve is wide open.精Secondary air pump relay J299通维Fuel tank修Exhaust flap下载 flapVacuum reservoirExhaust flap 1 valve N321377_025AEngine control unit (master) J623BEngine control unit 2 (slave) J62427
Air circulation systemVacuum hoses in the Audi Q7Secondary air pumpAir filterEvaporator casing extraction valveVacuum pump 精for brakes V192通维Suction jet pump 修(entrainment pump)with non-return valve下载 http://wwwCombination . servoBrake servo Brake servo pressure sensor G294relay J569AEngine control unit J62328
NoteThe illustrations show the vacuum hoses. The fitting locations may deviate from those shown air pump relay J299Evaporator casingfrom fuel tank精通维修下载 _06829
Fuel systemFuel system in the Audi Q7/RS4Fuel metering valve -2- N402Fuel meteringvalve N290High-pressurefuel pump 2精通High-pressurefuel pump 1维修下载 hFuel pressure sender, lotw pressure G410tpLeakage line://wwwLow-pressure system in the Audi an exact description of the system's ooperating mode, refer to SSP 325 - mAudi A6 ‘05 Engines and only different feature of this system is that it has high-pressure -pressure system in the Audi RS4High-pressureFuel filterLow pressuredepressurised30
Fuel pressure sender, high pressure G247Fuel distributor (rail) 2to the injectors of cylinders 5-8N83-N86Pressure limiting valve (136 bar)Fuel distributor (rail) 1Injectors, cylinders 1-4N30-N33精通维修下载 integrated inc tankom377_036Return lineFuel tankFuel pump (pre-supply pump) G6Fuel pump control unit J53831
Exhaust systemExhaust systemDuring the development of the exhaust system, special emphasis was placed on optimising flow resistance. The clamping flange system used in the -litre FSI engine has proved highly advantageous in this Q7Audi RS4Each cylinder bank has its own exhaust pipe. To enhance the sporty character of the RS4 engine, The air-gap insulated (LSI) exhaust manifolds are a fan-type manifold is used in the RS4. flanged onto the cylinder separation of the exhaust pulses is ensured They offer the advantage of low heat loss in the by keeping the individual exhaust pipes apart until exhaust gas. As a result of this, the primary catalytic they merge into one. These fan-type manifolds are converters are able to heat up quickly. also attached by means of the clamping flange The primary catalytic converters are ceramic type converters. The lambda probes are connected to them. The lambda probe upstream The primary and main catalytic converters are metal of the catalytic converter is a broadband probe. type catalytic converters. Their advantage is that A nonlinear probe is located downstream of the they have a lower flow resistance than ceramic catalytic converter. The main catalytic converters catalytic converters. This is good for engine in the underbody area are also ceramic catalytic performance.精converters. The exhaust pipes of the individual The front silencer for each of the exhaust pipes is 通cylinder banks discharge into a front silencer. housed in a common casing. 维The front silencer is an absorption-type silencer. However, the exhaust pipes are kept crossover function in the silencer ensures higher The front and rear silencers are absorption-type 修engine power output and torque. silencers. They are notable for their low flow 下The front silencer and the rear silencer are con-resistance.载nected by separate , the rear silencer is a common component of both exhaust pipes. On the inside of the rear tsilencer, however, the left and right exhaust pipes tpare clearly separated. Likewise, the rear silencer is :an absorption-type silencer.// system in the Q7coLSI exhaust manifoldmPrimary catalytic converterDecoupling elementMain catalytic converterFront silencerLambda probesRear silencer377_04432
Exhaust flap control Audi RS4A further difference is the layout; one exhaust flap is Function located downstream of each of the rear silencers. The exhaust flaps are fitted to give the engine a The exhaust flaps are switched by a vacuum sporty sound. The exhaust flaps are switched in actuator. Both vacuum units are switched by an such a way as to meet the statutory limits for electrically activated solenoid valve. The exhaust vehicle exterior noise. flaps are switched according to a characteristic map. Low-frequency droning noise at low engine RPM is prevented. At high engine RPM and high exhaust-The factors of engine load, engine RPM, gear gas flow rates, flow noise and exhaust backpressure selected and the shift signal from the Sport button are reduced by opening the additional cross-are used to plot the characteristic map. section. For example, the exhaust flaps are opened at idle The exhaust gas flaps are closed at idle, low engine when the Sport button is pressed. load and at low engine RPM.精通Exhaust system in the RS4维修Fan-type manifold, 4 in 2 in 1下载Primary catalytic converter htDecoupling elementtp:Main catalytic converter// silencerzweiLambda silencer377_046377_060Vacuum control actuatorExhaust actuator flap33
Exhaust systemSecondary air systemThe secondary air system ensures that the catalytic Operating mode in the Q7converter heats up more quickly and is available sooner after a cold start. During the warm-up phase, the engine control unit J623 activates secondary air pump V101 via the Principlesecondary air pump relay J299. The air flow from the secondary air pump opens the Due to the richer air-fuel mixture in the cold start combination valve for secondary air and admits air and warm-up phases, a higher concentration of into the exhaust system upstream of the catalytic unburned hydrocarbons occurs in the exhaust -oxidation in the manifold and headpipe is promoted by secondary-air injection. The heat dissipated during this process heats the catalytic converter to operating temperature within approx. 30 seconds after engine start.精通维修下Secondary air system in the Q7载 Air filterhttp:Secondary air pump //_043Combination valves (self-opening)34
Operating mode in the RS4The secondary air system operates in much the The basic engine in Q7 and the high-revving engine same way as that in the Q7 engine. The difference in RS4 have different fitting locations for the here lies in the way the combination valves open secondary air system. In the Q7 the secondary air and is fitted at the engine front end on the input side of the ribbed vee belt, while in the RS4 it is The air path from the secondary air pump to the fitted at the output end of the air duct in the cylinder head is opened by means of a vacuum unit on the combination valve. The vacuum unit is controlled by the secondary air inlet valve N112 via the engine control an exact description of the operating mode this system, please refer to SSP 217 - The V8 5V Engine.精通维修Secondary air system RS4下Air filterCombination valve with vacuum unit (vacuum controlled)载 airinjection valve N112Secondary air pump377_07435
Engine managementSystem overview - Audi Q7 (Bosch MED )SensorsAir mass meter G70Air mass meter 2 G246Intake air temperature sensor G42Accelerator pedal position sender G79Accelerator pedal position sender 2 G185Engine speed sender G28Knock sensors 1–4 G61, G66, G198, G199Fuel pressure sender G247Powertrain CAN data bus精通Intake manifold flap potentiometer G336Intake manifold flap potentiometer 2 G512维修下Hall sender G40Hall senders 2+3 G163, G300载Hall sender 4 G301 http:/Engine control unit J623/Fuel pressure sender, low pressure temperature sender valve module J338cThrottle valve drive angle senders -1- and -2-o(electric power control) G187, G188mLambda probe G39Lambda probe 2 G108Lambda probe after catalytic converter G130Lambda probe after catalytic converter 2 G131Coolant temperature sender -radiator outlet G83Brake light switch FBrake pedal switch F47Brake servo pressure sensor G294Additional signals:Cruise control system on/off from steering column electronics control unit J527Terminal 50/50 RBrake servoEntry and start authorisation control unit J518Convenience system central control unit J393 (door contact)Multi-function switch F125 (interlock /PN signal)Auxiliary heater wake-up via Climatronic control unit J25536
ActuatorsStarter motor relay J53, starter motor relay -2- J695Motronic current supply relay J271Engine component current supply relay J757Fuel pump control unit J538Fuel pump (pre-supply pump) G6Injectors, cylinders 1-8N30-N33, N83-N86Throttle valve module J338Throttle valve drive (electric power control) G186Ignition coils N70, N127, N291, N292, N323-N326Cylinders 1-8精通维Activated charcoal filter solenoid valve 1 N80修下Map-controlled engine cooling thermostat F265载 httpFuel metering valve N290:Fuel metering valve -2- N402//wwSecondary air pump relay J299wSecondary air pump motor camshaft timing adjustment valves 1+2 N205, N208eExhaust camshaft timing adjustment valves 1+2 N318, probe heater Z19cLambda probe 2 heater Z28 oLambda probe 1 heating, after catalytic converter Z29mLambda probe 2 heating, after catalytic converter Z30Variable inlet manifold motor V183Intake manifold flap motor V157Brake light suppression relay J508Continued coolant circulation relay J151Coolant run-on pump V51Fuel system diagnostic pump (USA) V144Brake servo relay J569Vacuum pump for brakes V192Radiator fan control unit J293 PWMRadiator fan V7Radiator fan control unit -2- J671Radiator fan 2 V177Additional signals:Engine speedClimatronic control unit J255377_02937
Engine managementSystem overview - Audi RS4 (Bosch MED )SensorsAir mass meter G70Intake air temperature sensor G42Accelerator pedal position sender G79Accelerator pedal position sender 2 G185Powertrain CAN data busEngine speed sender G28Knock sensors 1+2G61, G66Fuel pressure sender G247Hall sender G40Hall sender 3 G300Engine control unit J623 Throttle valve module J338(master)精Throttle valve drive angle senders 1+2 (electric power control) G187, G188通维修Clutch pedal switch F36Clutch pedal switch for engine sta下rt F194载 hCoolant temperature sender G62ttpFuel pressure sender, low pressure G410://wIntake manifold flap potentiometer probe G39gLambda probe after catalytic zconverter G130weiBrake servo pressure sensor light switch FmBrake pedal switch F47Starter button E378Additional signals:Cruise control system on/offTerminal 50Door contact wake-up from convenience system central control unit J393Engine control unit 2 J624 Hall sender 2 G163 (slave)Hall sender 4 G301Engine speed sender G28Knock sensors 3+4G198, G199Lambda probe 2 G108Lambda probe after catalytic converter 2 G131Intake manifold flap potentiometer 2 G512Additional signals:Door contact wake-up from convenience system control unit J39338
ActuatorsFuel pump control unit J538Fuel pump (pre-supply pump) G6Ignition coils N70, N127, N291, N292Cylinders 1–4Fuel metering valve N290Activated charcoal filter solenoid valve 1 N80Electro/hydraulic engine mounting solenoid valve, right N145Intake manifold flap air flow control valve N316Starter motor relay J53, starter motor relay -2- J695Exhaust flap 1 valve N321精Fuel system diagnostic pump (USA) V144 通维Injectors, cylinders 1–4N30–N33修下Inlet camshaft timing adjustment valve -1- N205Exhaust camshaft timing adjustment valve -1- N318载Throttle valve module J338 Throttle valve drive (electric power control) G186httContinued coolant circulation relay J151pCoolant run-on pump V51://Lambda probe 1 heater Z19wLambda probe 1 heating, after catalytic converter Z29wwVariable intake manifold change-over valve air pump relay J299DiagnosticeSecondary air pump motor V101connectioniSecondary air inlet valve servo relay J569oVacuum pump for brakes V192mEngine component current supply relay J757Motronic current supply relay J271Additional signals:Engine speedRadiator fan control unit J293 and J671Ignition coils N323-N326Cylinders 5-8 Inlet camshaft timing adjustment valve -2- N208Exhaust camshaft timing adjustment valve -2- N319Injectors, cylinders 5-8N83-N86Lambda probe 2 heater Z28Lambda probe 2 heating, after catalytic converter Z30Fuel metering valve -2- N402Electro/hydraulic engine mounting solenoid valve, left N144Throttle valve module J338377_03239
Engine managementEngine management in the new V8 FSI is by two The processor operates at a clock frequency of versions of the Bosch MED MHz. The internal memory has a storage capacity A single control unit is used in the Q7 engine. of 512 Kbytes. Each of the two external memories There are two control units for the RS4 engine. has a storage capacity of two master-slave concept is required here due to the The connection to the vehicle network is made requisite processing power at engine speeds up to by means of a CAN data the case of the master-slave concept, data is additionally exchanged across a private differences between the Q7 and RS4 engines in respect of engine management are as follows:Engine speed sender G28 An inductive sender is used in the Q7 engine. A Hall sensor is used in the RS4 engine with master-slave concept. 精The signal from the Hall sender, can unlike the signal fr通om the inductive sender, be split with the result that it can be utilised by both engine control 维377_067units.修Applying the signal directly to both engine control units ensures that the con下trol units are absolutely in sync.载 htThrottle valve moduletp:The Bosch throttle valve module used in the Q7 is //the largest in the range with a diameter of 82 mm. wThe Pierburg system was selected because the air wwintake system in the RS4 has a diameter of 90 mm. .However, both systems work in exactly the same plugsomIn contrast to the Q7, spark plugs with a higher heat rating (colder plugs)* are used because the RS4 engine is subjected to higher thermal stresses.* applies to NGK spark plugs377_071InjectorsDue to the higher fuel demand and the shorter time window available for injection at very high engine speeds, the RS4 engine is fitted with larger injectors than the Q7 engine. 377_066DiagnosisThe RS4 engine is diagnosed via the K-wire. The Q7 is diagnosed via the powertrain CAN
Communications between control units in the RS4The engine control unit (master) J623 computes Master and slave control units are identical in and controls the signals from the actuators for design and have the same part number. cylinder bank 1. A voltage code in the control unit determines Most sensors are connected to the engine control whether the control unit in the master or the slave. unit (refer to System overview, pages 38/39). Both control units are connected to the CAN data If battery positive is applied to the encoding pin, the bus; the slave control unit is used as a receiver only. control unit is the load signals required to compute and control the signals for the actuators of cylinder bank 2 are transmitted via private bus. The slave control unit acts as the misfire detector for each of the eight cylinders. It also processes the signal from the engine speed sender unit 1 - masterControl unit 2 - slave精通维修下载 http:Private/ bus / data busgzwe377_064ixOperating - high-pressure stratified charge startmInjection of the metered fuel mass begins during In comparison to the low-pressure start system, the compression stroke phase and ends shortly homogenisation is greatly improved by utilising the before the firing of compression for carburetion, and HC emis-sions are start - HOSP = homogeneous splitApplication:– Mixture combusts very late– Heating the primary catalytic converters to – Exhaust valve already open 300 °C in approx. 12 sec.; lambda value – Intake manifold flap position: closedAs a result, the cat reaches its operating tempera-– Throttle valve position: wide openture very :Normal operation homogeneous carburetion– First injection approx. 300° before ignition TDC– Second injection of small amount of fuel approx. (lambda 1) with open or closed intake manifold flap 60° before ignition TDC, retarded ignition timing(map based)41
Engine managementCAN data bus interfaces (powertrain CAN data bus) in the Audi Q7The messages listed here are transmitted from the control units to the powertrain CAN data bus. However, only a few of the important messages are listed. In reality, there are many more. Of course, these messages are subject to change due to software control unit (master) J623Automatic gearbox control unit Data bus diagnostic Transmits:J217interface J533Idle information (EBC)Transmits:Trailer operationKick-down informationSelector active/inactiveRear lightEngine speedAir conditioner compressor "OFF"Brake lightEngine torqueTorque converter lock-up clutch Trailer brake lightAccelerator pedal anglestatusAuxiliary heater activeMechanical engine torque lossTarget gearAll relevant ACC messages Gearbox codeSelector lever positionfrom J428Engine configurationNOMINAL engine torqueAll relevant CCS messages Coolant temperatureMotion resistance indexfrom J523Brake light switch informationLimp-home programsAlternator load torque精Brake pedal switchCooling requestClimatronic J255:通CCS switch positionsOBD status (MIL lamp activation)-Request维CCS set speedIdle input torque- RPM increaseSET/ACTUAL idle sp修eedRev-up flag- Torque increaseThrottle-valve angleNominal idling speedDash panel insert J285:下Intake air temperatureCreep adaptation mode request- Fuel tank information载Drive-by-wire throttle lampHazard warning light system "on"- Ambient temperature OBD2 lampGear shift active- Standing time ht"Hot" warning lamp- MileagetpPower reduction or - Information from oil level/:air conditioner compressor load /oil temperature sender G266/sheddingwwFuel fan activationgOil temperaturezwFault memory entryeiActivation of electrical CAN Highxbrake servo LowABS control unit 104TCS requestEBC requestABS requestEDL interventionSteering angle sender G85ESP interventionSteering wheel angle (utilised for ESP brake light switchidling pre-control and engine Active brake servotorque calculation based on Road speed signalthe power demand of the power TCS intervention torquesteering system)Ride height control J197EBC intervention torqueTorque request at full steering V-limit Lateral accelerationlockin case of falsely set code 80 kphWheel speedBrake pressure status42
CAN data bus interfaces (powertrain CAN data bus) in the Audi RS4Engine control unit (master) J623ABS control unit J104Control unit with display in dash Idle informationTCS requestpanel insert J285Accelerator pedal angleEBC requestRear lightClutch switchABS requestSteering column electronics Engine torqueEDL interventioncontrol unit J527:Engine speedESP interventionAll relevant CCS messages Coolant temperatureESP brake light switchSport switchBrake light switch informationRough road suppressionClimatronic J255:CCS statusABS in diagnosticsAll signals which require load Throttle-valve angleActive brake servoadaptation due to a load air temperatureRoad speed signalDash panel insert J285:OBD2 lampTCS intervention torque- Fuel tank information精"Hot" warning lampEBC intervention torque-Oil temperature通Air conditioner compressor "OFF" or TCS lamp activation- Ambient temperature维power reductionLateral acceleration- Standing time Starter control (automatic修 start)Wheel speed- MileageOil temperature-Information from oil level/ 下oil temperature sender G266载 http://wwwCAN LowcomCAN 2 CAN 2 LowHighEngine control unit 2 (slave) J624Utilises the signals fromSteering angle sender G85CAN 1 (powertrain CAN bus) and Steering wheel angle and CAN 2 (private CAN) to calculate steering wheel angle speed the activation of the actuators of (utilised for idle pre-control cylinder bank 2 (left bank) (refer and engine torque calculation to System overview).based on the power demand Airbag control unit J234of the power steering system)Crash intensityFuel shut-off43
Engine managementStart mode of the Audi RS4Start button(starter button E378)The RS4 is equipped with a Start button (except When a repeat attempt is made to start the models for USA, Canada and Korea). (e. g. stalled) engine, the ignition key does not have It is located in the centre console adjacent the to be turned back. The vehicle can be restarted handbrake lever. The engine is started by briefly straight the switch when the ignition is "on". Operating the Start button when the engine is The Start button is a simple NO contact and running has no effect as the Start button is disabled switches the terminal 15 signal through to the by the engine control unit when engine RPM is engine control unit J623 when terminal 15 is alternately switching off the starter relay after Apart from the fact that the start contact has been engine start, the engine control unit can determine moved to the Start button, the functions of the whether either of the two relays is "sticking". ignition lock are the same as in the A4. The ignition Function testing both relays ensures that the starter lock is disabled in the starting always switched off after engine start and there-To start the engine, the signals from the clutch fore de-meshes. 精pedal switch F36 and the clutch pedal switch for If a relay does fails to open due to "sticking", current engine starting F194 must also be present. flow is nevertheless interrupted by the opening of 通When the clutch is depressed, the F36 recognises the second relay. In this case a fault is entered in the 维that the clutch pedal has left its rest position and engine control unit memory.修opens. The F194 is actuated, . closed, when the clutch is 下fully depressed.载Because one switch opens and the other closes, the engine control unit can verify the redundancy of hboth switches. ttThe cruise control system also utilises the signal pfrom the F36.://_07044
303087871515SSSSDE378F194F36精通维J623J624修下载 ht5Vt+-S3015a50J695p:MJ53G/28B/_076mLegend of function diagramBStarterG28 Engine speed senderD Ignition switchJ53Starter motor relayE378Starter buttonJ623Engine control unit (master)J624Engine control unit 2 (slave)F36Clutch pedal switchJ695Starter motor relay -2-F194Clutch pedal switch for engine start45
Engine managementSport mode of the Audi RS4To accentuate the sporty character of the RS4, the Depending on steering wheel type, the sport driver can switch Sport mode "on" of "off" using a program button is fitted in different vehicles equipped with the RS sport steering wheel, the Sport program button is located in the left steering wheel spoke; in models equipped with a multifunction steering wheel, it is located in the centre Sport mode is activated, an indicator lamp comes on in the dash panel mode is deactivated when the ignition is turned _077精通When the Sport program button is pressed the 维following in-vehicle functions are activated:修– more direct accelerator pedal response下– improved lateral support function of the driver's 载seat – more sporty exhaust system set-uph377_078ttp://wAccelerator pedal function ww(throttle progression).gzWhen Sport mode is activated, the engine becomes In addition the comfort-oriented "soft" engine wmore responsive. At the same time, the characteris-torque curve is suppressed. As a result, the engine itic curve of the accelerator pedal is modified in the responds immediately to pressure on the control unit. This means that, in Sport mode, tor requested engine torque is higher than in omnormal operation in the same accelerator pedal operation100Sport mode9080706050403020100102030405060708090100Accelerator position46Requested torque in %
Seat functionExhaust flap controlThe improved lateral support function of the After the Sport mode is activated, unlike in normal front seats is only available in combination with operation, the exhaust flaps in the rear silencer are RS bucket when the engine is idling. This emphasises the sporty sound of the RS4 engine. The backrest and side seat bolsters are inflated. The seat bolster inflation function can be set After the engine speed is increased, however, the manually using the buttons on the seat. exhaust flaps are closed again. This ensures that the When the Sport button is pressed, only the driver's vehicle meets the statutory noise emission limits. seat side bolster are inflated. If a certain limit has Reopening of the exhaust flaps while driving is been preset manually, then the bolsters will be speed and load dependent, and is regulated on the inflated up to this of a characteristic Sport mode is turned off, the bolsters are deflated (approx. two sec.). The sport seat function can be deactivated by the driver as necessary. The procedure is described in the vehicle's Owner's Manual.精通维修Note下The sport seat function is deactivated 载automatically after the vehicle battery terminals are disconnected. The sport seat hfunction must be reactivated if this has ttbeen set by the ://www377_079Function of the sport program -function steering wheel control unitweixWhen the sport program button E541 in the centre The steering column electronics control unit .console is pressed, a terminal 15 signal is transmit-converts the signal and sends this message to the coconvenience CAN to the steering column electronics control unit mJ527 across a discrete message is transmitted via the gateway in the dash panel insert and is evaluated by the control RS sport steering wheelunit with display in dash panel insert J285. A check is made to determine whether the sport seat function has been activated. The signal from the sport program button is If the function is active, a message to this effect is transmitted from the multi-function steering wheel transmitted across the convenience CAN bus to the control unit J453 across the LIN bus to the steering seat and steering column adjustment control unit column electronics control memory J136, and the driver's seat backrest and side bolsters are inflated or deflated for two gateway also transmits the message "Sport button pressed" to the powertrain CAN bus. The engine control unit adapts the throttle progression and exhaust flap control based on this details of the bus topology, please refer to SSP 343 - The new Audi A4 ‘
377 Vorsprung durch Technik Training精通维修下载 -litre V8 FSI engineSelf-Study Programme 377All rights reserved. Technical specifications subject to change without AGI/@ +49-841/89-36367AUDI AGD-85045 IngolstadtTechnical status: 03/06Printed in
