Tài liệu hệ thống nhiên liệu common rail - ford

Tài liệu hệ thống nhiên liệu common rail - xe ô tô ford

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Common Rail Systems

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No part of this publication may be reproduced, stored in a data processing system or transmitted in any form, electronic, mechanical, photocopy, recording, translation or by any other means without prior permission of Ford-Werke GmbH No liability can be accepted for any inaccuracies in this publication, although every possible care has been taken to make it as complete and accurate as possible.

Ford-Werke GmbH

Service training programs D-F/GT1 (GB)

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More stringent exhaust and noise emission standards and requirements regarding lower fuel consumption continue

to place new demands on the fuel injection and engine management system of diesel engines

In order to satisfy these requirements, the injection system must inject the fuel at high pressure into the combustionchamber to provide good mixture preparation and, at the same time, meter the injected fuel quantity with the highest

possible accuracy The Common Rail System offers good potential for development, which is of particular

significance both now and in the future By separating the pressure generation process from the injection process,the optimum injection pressure is always available for the injection process, regardless of engine speed

The newly developed engine management system ensures that the fuel injection timing and injected fuel quantityare calculated exactly, and that the fuel is delivered to the engine cylinders by the piezo-controlled fuel injectors

The following common rail systems are currently used in Ford vehicles:

– Delphi common rail system,

– Bosch common rail system,

– Siemens common rail system,

– Denso common rail system

Another big step towards achieving cleanliness in diesel engines is the newly developed diesel particulate filtersystem This system helps reduce micro-fine diesel particulates by up to 99%

Completion of the eLearning program "Diesel Fuel Injection and Engine Management Systems" is a prerequisitefor the study of this Student Information

This Student Information is divided into lessons The objectives that should be met by working through the lessonare set out at the beginning of each lesson At the end of each lesson there is a set of test questions which aredesigned to monitor the student's progress The solutions to these test questions can be found at the end of theStudent Information

Please remember that our training literature has been prepared for FORD TRAINING PURPOSES only Repairsand adjustments MUST always be carried out according to the instructions and specifications in the workshopliterature Please make full use of the training offered by Ford Technical Training Courses to gain extensiveknowledge of both theory and practice

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1 Preface

Lesson 1 – General Information

13 Objectives

14 Overview of the Systems

17 Introduction

18 Injection characteristics

21 Emission Standard IV with or without diesel particulate filter

21 Cleanliness when working on the common rail system

22 EOBD (European On-board Diagnostic)

22 General

23 Fault logging and storing

25 Engine Emission Control

25 Pollutant emissions reduction

27 Test questions

Lesson 2 – Delphi-Common Rail System

29 Objectives

30 Overview of the two-module system – system with PCM and separate IDM

32 Overview of the single-module system – system with one PCM (IDM integrated in the PCM)

33 Characteristics

33 Special features

34 Service instructions

34 EEC V powertrain control module PCM (two-module system)

36 IDM (two-module system)

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37 Delphi PCM (single-module system)

38 Glow plug control

40 Sensors

40 CKP sensor

41 CMP sensor

42 MAP/IAT and T-MAP sensor

43 CHT sensor

45 MAF sensor

45 VSS

46 APP sensor

47

KS

47 Fuel temperature sensor

48 Fuel pressure sensor

48 Fuel pressure outside the specified range

49 Position sensor in vacuum-operated EGR valve

50 Position sensor in electric EGR valve

51 Switch

51 Stoplamp switch/BPP switch

51 CPP switch

52 Actuators

52 Fuel metering valve

53 Fuel injector solenoid valve

55 EGR solenoid valve and boost pressure control solenoid valve

55 Intake manifold flap and intake manifold flap solenoid valve

56 Electric EGR valve (certain versions only)

58 Electrical turbocharger guide vane adjustment actuator

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61 Strategies

61 Ignition ON strategy

61 Engine start strategy

64 Idle strategy

64 Idle speed control

65 Fuel metering calculation

68 Smooth-running control (cylinder balancing)

68 External fuel quantity intervention

68 Controlling fuel injection

70 Controlling the fuel pressure

72 EGR system

75 Boost pressure control

77 PCM fault strategy

77 Monitoring the system

79 Coated diesel particulate filter

79 Overview – diesel particulate filter

80 Passive regeneration

80 Active regeneration

81 Notes on the oil change interval

82 Emission control components

83 Exhaust gas temperature sensors

83 Diesel particulate filter differential pressure sensor

85 MAP sensor

85 Intake manifold flap and intake manifold flap solenoid valve

86 Intake manifold flap position sensor

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87 Fuel System

87 Overview

88 General

89 Fuel filter

90 Overview – high-pressure system

91 High pressure pump

95 Fuel rail (common rail)

96 Excess pressure safety valve

97 High-pressure fuel lines and leak-off pipes

97 Fuel injectors

Lesson 3 – Bosch-Common Rail System

103 Objectives

104 Overview

105 Characteristics

106 PCM

110 Sensors

110 CKP sensor

110 CMP sensor

111 MAP sensor

112 BARO sensor

112 ECT sensor

114 Combined IAT sensor and MAF sensor

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115 Vehicle speed signal

115 APP

116 Fuel temperature sensor

118 Switch

118 Oil pressure switch

118 Stoplamp switch/BPP switch

118 CPP switch

119 Actuators

119 Fuel metering valve (CP3.2)

120 Fuel metering valve (CP1H)

123 Boost pressure control solenoid valve

124 EGR valve

125 Intake manifold flap servo motor (vehicles with diesel particulate filter)

128 Strategies

128 Regeneration process

130 EGR system

134 Other strategies

135 Diesel particulate filter with fuel additive system

135 Component overview

136 Diesel particulate filter

138 Intercooler bypass

140 Fuel additive system – general

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141 System components – fuel additive system

143 Component overview – system control

144 Control modules

145 Fuel additive pump unit

146 Tank flap switch

147 IAT sensor

147 Exhaust gas temperature sensor

148 Diesel particulate filter differential pressure sensor

150 Intake manifold flap servo motor

150 Intercooler bypass flap servo motor

152 Fuel System

152 Overview

153 General

154 Fuel filter

163 High pressure fuel lines

163 Fuel injectors

Lesson 4 – Siemens-Common Rail System

169 Objectives

170 Overview

173 Characteristics

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173 Special features

174 PCM

177 Sensors

177 MAP sensor

178 IAT sensor

179 BARO sensor

180 Turbocharger position sensor (certain versions only)

180 ECT sensor

181 CHT sensor (1.8L Duratorq-TDCi (Kent) diesel only)

182 Combined IAT sensor and MAF sensor

183 Vehicle speed signal

184 APP sensor

185 Vacuum-operated intake manifold flap position sensor (certain vehicles with emission standard IV)

187 Other sensors

188 Switch

188 Information

189 Actuators

191 Fuel pressure control valve

194 Piezo-electric control of fuel injectors

196 Boost pressure control valve (variable geometry turbocharger, vacuum-controlled)

199 Intake manifold flap and intake manifold flap solenoid valve (vacuum-operated systems)

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200 Intake manifold flap servo motor (1.4L Duratorq-TDCi (DV) diesel engine, emission standard IV)

200 EGR valve solenoid valve (vacuum-controlled systems)

201 EGR valve (electrically controlled systems)

204 Engine warm-up regulation(only 2.0L Duratorq-TDCi (DW) diesel engine)

204 Note

204 Component locations

205 Principle of operation

210 Other strategies

211 Diesel particulate filter with fuel additive system

211 Note

211 Component overview

212 Diesel particulate filter

213 Intercooler bypass

215 Component overview – system control

216 Exhaust gas temperature sensors

218 Intake manifold flap and intercooler bypass flap solenoid valves

220 Coated diesel particulate filter

220 Overview – diesel particulate filter

221 Emission control components

222 Intake manifold flap, intake manifold flap position sensor and intake manifold flap solenoid valve

223 Siemens system

223 Overview

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224 General

225 Fuel filter

226 Manual pump

227 High-pressure system – general

232 Fuel rail (common rail) and high pressure fuel lines

234 Fuel injectors

Lesson 5 – Denso-Common Rail System

241 Objectives

242 Overview

243 Notes on this lesson

243 Characteristics

244 PCM

246 Sensors

246 MAF sensor

246 APP sensor

247 Oil level/temperature sensor

250 Actuators

254 Fuel system

254 Overview

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255 General

255 Fuel filter

262 Fuel injectors

265 Answers to the test questions

266 List of Abbreviations

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On completing this lesson, you will be able to:

• explain the advantages of the common rail system

• state the reasons for the use of pilot injection

• explain what effect pilot injection has on combustion

• state the reasons for the use of post-injections

• explain which types of post-injections are used

• explain the purpose of the EOBD system

• name the different monitoring systems of the diesel EOBD system

• explain the fault detection and storage of emission-relevant faults

• state the reasons for the use of the diesel particulate filter

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Overview of the Systems

Delphi common rail system

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Bosch common rail system

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Siemens common rail system

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Denso common rail system

Introduction

Increasingly higher demands are being placed on modern

diesel engines The focus is not only on exhaust

emissions but also on increasing environmental

awareness and the demand for increasingly better

economy and enhanced driving comfort

This requires the use of complex injection systems, highinjection pressures and accurate fuel metering by fullyelectronically-controlled systems

The high injection pressures convert the fuel, via theinjector nozzle, into tiny droplets, which, again due tothe high pressure, can then be optimally distributed inthe combustion chamber This results in fewer unburned

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HC (Hydrocarbon)s, less CO (Carbon Monoxide) and

fewer diesel exhaust particulates being produced in the

subsequent combustion stage

In addition, the optimized mixture formation reduces

fuel consumption

Diesel knock caused by the combustion process of an

engine with direct injection is significantly reduced by

means of additional pilot injection (pilot injection) NOX

(Oxides Of Nitrogen) emissions can also be reduced by

using this method

Demands for better driving comfort also influence the

requirements placed on today's diesel engines In

particular, the importance of noise and exhaust

emissions continues to increase This leads to increased

demands being placed on the injection system and its

control, e g.:

• high injection pressures,

• shaping of injection timing characteristics,

• pilot injection,

• injected fuel quantity, start of injection and boost

pressure values adapted to every operating condition,

• load-independent idle speed control,

• closed loop EGR (Exhaust Gas Recirculation),

• low injection timing and injected fuel quantity

tolerances and high degree of precision for the entire

service life,

• options to interact with other systems, such as the

Electronic Stability Program, PATS (Passive

Anti-theft System),

• comprehensive diagnostic facilities,

• substitute strategies in the event of faults

The common rail injection system has a large range

of features to meet these demands

In common rail injection systems, pressure generation

is separate from the injection process The injection

pressure is generated independently of engine speed and

injected fuel quantity

The common rail injection system consists of ahigh-pressure pump and a fuel rail (fuel accumulator).The fuel in this fuel rail is at a constant pressure and isavailable for distribution to the electrically controlledfuel injectors

With this type of diesel injection or engine managementsystem, the driver does not have a direct influence onthe quantity of injected fuel, because, for example, there

is no mechanical connection between the acceleratorpedal and the injection pump Here, the injected fuelquantity is determined by various parameters Theseinclude:

• driver demand (accelerator pedal position),

• operating state,

• engine temperature,

• effects on exhaust emissions,

• prevention of engine and transmission damage,

• faults in the system

Using these parameters, the injected fuel quantity iscalculated in the PCM and fuel injection timing andinjection pressure can be varied

The fuel is metered fully electronically via piezoelements controlled by the PCM which are locateddirectly in the fuel injectors

The fully electronic diesel engine management systemfeatures a comprehensive fail-safe concept (integrated

in the PCM software) It detects any deviations andmalfunctions and initiates corresponding actionsdepending on the resulting effects (e.g limiting thepower output by reducing the quantity of fuel)

Injection characteristics

As already mentioned at the beginning of the lesson,

the exhaust emissions and fuel consumption of an

engine are of great significance These factors can only

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be minimized through precise operation of the injection

system and comprehensive engine management

strategies

Consequently, the following requirements must be met

by the common rail system:

• The injection timing must be exact Even small

variations have a significant effect on fuel

consumption, exhaust emissions and combustion

noise

• The fuel injection pressure is independently adapted

to all operating conditions

• Injection must be terminated reliably Calculation

of the injected quantity and the injection timing is

precisely adapted to the mechanical components of

the injection system Uncontrolled fuel dribble (for

example, caused by a defective fuel injector) results

in increased exhaust emissions and increased fuel

consumption

Simple main injection:

Needle lift of fuel injector nozzle and pressure curve in the cylinder without pilot injection

Combustion pressure in the cylinder1

Needle lift2

TDC (Top Dead Center)3

Needle lift for simple main injection4

Crank angle5

In the case of diesel engines with a distributor-type

fuel injection pump (for example in the Transit 2000.5),

the fuel injection on the pump-side is via simple maininjection

The fuel is then injected mechanically into the

combustion chamber by the injector nozzles in twoseamlessly integrated stages (two-spring nozzle carrierprinciple)

In the pressure curve, the combustion pressure increasesonly slightly in the phase before TDC, corresponding

to compression, but increases very sharply at the start

of combustion

The steep pressure rise intensifies the combustion noise

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Pilot injection

Needle lift of fuel injector nozzle and pressure curve in

the cylinder with pilot injection

Combustion pressure in the cylinder

In the case of vehicles with common rail injection

systems electrically-controlled pilot injection occurs

after a set time prior to the main injection event

In the case of pilot injection, a small amount of fuel is

injected into the cylinder prior to the main injection

Pilot injection results in a gradual increase in the

combustion pressure, leading to an improvement in

combustion quality

The small, pilot injection fuel quantity is ignited and

heats up the upper part of the cylinder, thereby bringing

it into an optimum temperature range (pre-conditioning

of the combustion chamber)

This means that the main injection mixture ignites morequickly and the rise in temperature is less abrupt as aresult

This also results in a less abrupt increase in combustionpressure, significantly reducing combustion noise

Advantage:

• Continuous build-up of combustion pressure,resulting in reduced combustion noise,

• Reduction of nitrogen oxides in the exhaust gas

Note: As pressure generation and injection in common rail systems are separate, it is possible to considerably

enhance the range for pilot injection (up to approx 3000rpm regardless of engine load) This has led to a decisiveimprovement in the running characteristics of the engine

Post-injection (vehicles with diesel particulate filter system)

Needle lift of injector nozzle with pre- and post-injection

Needle lift1

Pilot injection2

Crank angle3

Main injection4

Advanced post-injection5

Retarded post-injection6

For vehicles with a diesel particulate filter system two

post-injections are employed during the regeneration

process, in addition to the pre- and main injections,depending on the requirements

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Advanced post-injection is initiated in certain

load/speed ranges immediately after main injection

Fuel is then injected during the ongoing combustion

The main purpose of this advanced post-injection is to

raise the exhaust gas temperature during the regeneration

process of the particulate filter In addition, some of the

diesel particulates produced during regeneration are

after-burned

Retarded post-injection only occurs shortly before

BDC (Bottom Dead Center) and also serves to raise the

exhaust gas temperature

In contrast to the previous injections, during retarded

post-injection the fuel is not burnt, but evaporates due

to the residual heat in the exhaust gas This exhaust/fuel

mixture is delivered to the exhaust system by the exhaust

stroke

In the oxidation catalytic converter, the fuel vapor reacts

with the residual oxygen (above a certain temperature)

and burns This provides sustained heating of the

oxidation catalytic converter, which supports the

regeneration of the particulate filter

Emission Standard IV with or without

diesel particulate filter

At the time of going to press emission standard IV

applies in Europe

In the diesel sector, emission standard IV is achieved

using two different methods

One method consists of reducing exhaust emissions by

means of internal engine measures to the extent that

the prescribed limit values are met

Measures for the reduction of exhaust emissions insidethe engine include, for example:

• further optimized exhaust gas recirculation by means

of an electrically controlled EGR system with intakeair restriction,

• optimization of the combustion chamber design andthe injection characteristics

In addition to optimization through internal engine

measures, the second method employs a diesel

particulate filter system.

With the use of diesel particulate filters, dieselparticulate emissions are reduced by more than 99%

This reduction far exceeds the requirements for the

European emission limits of emission standard IV

It can therefore be assumed that the use of the dieselparticulate filter will be of great importance with regard

to future emission standards, but is not absolutely

necessary for meeting emission standard IV

Cleanliness when working on the common rail system

NOTE: Because the components of the high-pressure

fuel system are high-precision machined parts, it isessential that scrupulous cleanliness is observed whencarrying out any work on the system

In this regard, refer to the instructions in the currentService Literature

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The EOBD system does not use any additional sensors

or actuators to individually measure pollutants in the

exhaust emissions

The EOBD system is integrated into the software of the

PCM and uses the existing sensors and actuators of the

engine management system

With the aid of these sensors, actuators and the special

software, systems and components significant for

emissions are continually checked during the journey

and exhaust emissions calculated accordingly

Components significant for emissions are checked with

the so-called monitoring system.

With the introduction of EOBD for European Ford diesel

engines as of 1 January 2004 this will comprise the

following monitoring systems (monitors):

• monitoring of components significant to emissions

(Comprehensive Component Monitors = CCM),

• monitoring of the EGR system,

• boost pressure monitoring,

• fuel pressure monitoring

Monitoring system for components significant for exhaust emissions (CCM)

The monitoring system for components significant foremissions (CCM) continually checks to see if the sensorsand actuators significant for emissions are operatingwithin the specified tolerances when the engine isrunning

If a sensor or actuator is outside the tolerance range,this is recognized by the monitoring system and a DTC

is stored in the data memory

Monitoring of the EGR system

The operation of the EGR system is monitored toidentify faults that lead to increased exhaust emissionsand may exceed the EOBD threshold values

This monitoring system was developed so that it can,among other things, check the flow characteristics ofthe EGR system

Boost pressure monitoring

Boost pressure control operates via the boost pressurecontrol solenoid valve and the MAP (Manifold AbsolutePressure) sensor in a closed control loop

The boost pressure is constantly monitored via the MAPsensor

Fuel pressure monitoring

Fuel pressure monitoring operates via the fuel meteringvalve and the fuel pressure control valve Feedbackregarding the current fuel pressure is received via thefuel pressure sensor

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MIL (Malfunction Indicator Lamp)

The MIL is located in the instrument cluster and shows

an engine icon (international standard)

The MIL warns the driver that the EOBD system has

detected an emissions-related fault in a component or

system

If an emissions-related fault is detected and if this fault

is confirmed during the third driving cycle, the MIL

is switched on

After the MIL has been switched on, a fault log is

created in the PCM The fault logs contain information

regarding the type of fault and the time since the MIL

was activated

The MIL ensures that a fault is recognized in time The

defect can be repaired in good time and the emission of

exhaust gas with high levels of pollutants is avoided

Fault logging and storing

A fault occurring for the first time is labeled in the freeze

frame data as a suspected fault (pending code) and is

stored in the data memory

If the fault is not confirmed in the next check, it is

erased

If it is confirmed during the third drive cycle, thesuspected fault is automatically converted into a

confirmed fault (continuous code) The freeze frame

data does not change It remains the same as when thefault first occurred

The MIL only illuminates when the fault has been stored

as a confirmed fault

If the fault does not recur in the course of threeconsecutive drive cycles, the MIL extinguishes in thefourth drive cycle However, the fault code remainsstored in the data memory

Faults which do not reoccur are automatically clearedfrom the memory after 40 warm-up cycles

If a faulty signal is detected during a journey and thecorresponding fault code is stored, all the checks inwhich this signal is required as a comparison variableare interrupted This prevents follow-up faults frombeing stored

Diagnostic trouble codes can be read or cleared withthe WDS ( Worldwide Diagnostic System) Forddiagnostic tester

Drive cycle

A drive cycle commences when the engine starts (enginecold or hot) and ends when the engine is stopped.Depending on the complexity of the fault, themonitoring period may vary:

• For simple electrical faults, a monitoring period ofless than five minutes is sufficient

• For the purpose of monitoring a system (for examplethe EGR system) where different operating

conditions etc are required to complete the test, thetest can take up to about 20 minutes

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Warm-up cycle

A warm-up cycle starts when the engine is started, at

which point the coolant temperature must be at least 22

°C, and ends as soon as the coolant temperature exceeds

70 °C

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Pollutant emissions reduction

Maximum exhaust emission levels for passenger vehicles in grams per kilometer (g/km)

Particulate matter (PM) (g/ km)

HC + NOX NOX (g/km)

HC (g/km)

CO (g/km)

0.050.56

0.50-

0.64

Emission

Standard III

0.0250.30

0.25-

0.50

Emission

Standard IV

0.18-

1.200.40

3.20

EOBD limits

In order to meet the increasingly stringent emission

standards, exhaust gas after treatment will increase in

significance even for diesel engines, despite the progress

made with regard to engine modifications

By constantly improving the injection systems (direct

injection in conjunction with constantly increasing

injection pressures) and their electronic control, the

performance, economy and comfort of the diesel engine

has steadily been increased

Also of significance is the reduction of exhaust gas

emissions, the maximum levels of which have to be

continuously improved due to legal requirements

The measures inside the engine (high injection

pressures, nozzle design, timed introduction of fuel and

combustion chamber shape) have lowered the CO, HC

and diesel particulate emissions to a large extent

The NOX emissions produced by excess air in diesel

combustion are effectively reduced by exhaust gas

recirculation systems which are constantly being

improved

The oxidation catalytic converter, in use for some

years now, represents the first stage of exhaust gas

aftertreatment It further reduces HC and CO

emissions

Diesel particulate matter

As previously mentioned, a considerable reduction indiesel particulate matter has already been achieved bymodifications to the engine

Since the introduction by the EU Commission in 1989

of the first emission standard for diesel passengervehicles, the limit for diesel particulates has beenreduced from 1.1 g/km by a factor of 22 to only 0.05g/km today (Emission Standard III)

With regard to Emission Standard IV (0.025 g/km) it isbecoming clear, however, that the means by which dieselparticulate emissions can be reduced through enginemodifications have been virtually exhausted

A further incentive for achieving a reduction isincreasing environmental awareness and the fact thatthe residual diesel particulate matter has a harmful effect

on the human body

Diesel particulates are composed mainly of a chain ofcarbon particles (soot) with a very large specific surfacearea

The noxious effect of diesel particulate matter is a result

of adsorption of unburned or partially burned HC Inaddition, fuel and lubricant oil aerosols (solid or liquid

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substances finely distributed in gases) and sulphates

(depending on the sulphur content of the fuel) bind with

the soot

Diesel particulate filter

Starting from model year 2004.75, a diesel particulate

filter system for exhaust gas after-treatment will be used

for the first time on Ford vehicles with diesel engines

(initially only as an option on the Focus C-MAX)

By using appropriate filter materials it is possible to

retain in the filter more than 99 % of the diesel

particulates that are still emitted today.

With this method almost all of the particulates can be

retained, however the complete removal of diesel

particulates using conventional catalytic methods is not

possible The diesel particulates are deposited in the

diesel particulate filter

As the collection capacity of the diesel particulate filter

is only limited, it has to be regenerated at regular

intervals

Intervention in engine management system

During regeneration, comprehensive closed-loop control

circuits are activated in the engine management system

depending on different temperatures and pressures

To achieve the necessary temperature for regeneration,

different operations are performed (for example

throttling the intake air, post-injections)

These operations serve to raise the exhaust gas

temperature while keeping the added fuel consumption

as low as possible

Fuel additive

With some diesel particulate filter systems the

temperature for combusting the diesel particulates is

lowered by approx 100 °C by adding a fuel additive.

Coated diesel particulate filter

The filter material of this diesel particulate filter iscoated with a precious metal This precious metalcoating helps to convert the diesel particulatescatalytically at a temperature of 300 450 °C

However, it is often not possible to attain temperaturesthis high in urban traffic In this case, the dieselparticulates are deposited in the diesel particulate filter

To burn them off, regeneration must be initiated atregular intervals by an intervention into the engineregulation

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Tick the correct answer or fill in the gaps.

1 What is the advantage of the common rail system?

a The high injection pressures reduce combustion temperatures; exhaust gas recirculation is not required

b Pressure generation and injection are separated

c The injection pressure is generated as a function of engine speed

d Combustion noise is substantially reduced as a result of indirect injection

2 What is the effect of pilot injection?

a Pilot injection results in an abrupt build-up of combustion pressure and therefore reduced combustion noise

b Pilot injection results in an abrupt build-up of combustion pressure and therefore increased combustionnoise

c Pilot injection results in a gradual increase in the combustion pressure

d Pilot injection only results in a reduction of fuel consumption

3 Where are post-injections utilized?

a in vehicles with an electric EGR system

b in vehicles with an NOX catalytic converter

c in vehicles with no diesel particulate filter system

d in vehicles with a diesel particulate filter system

4 When does the MIL indicate an emissions-related fault?

a Immediately after the emissions-related fault has occurred

b If an emissions-related fault has been confirmed after the second consecutive drive cycle

c If an emissions-related fault has been confirmed after the third consecutive drive cycle

d If the emissions-related fault has been confirmed after the second warm-up cycle

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On completing this lesson, you will be able to:

• name all the engine management components

• explain the difference between the two-module system and the single-module system

• explain how the glow plug control system works and be able to identify fault symptoms

• explain the task and function of the individual engine management components

• describe some fault symptoms when individual components malfunction

• explain various strategies of the engine management system

• draw conclusions about possible faults in the engine management system

• name the components of the diesel particulate filter system and be familiar with their function

• explain how the diesel particulate filter system works

• name the components of the fuel and injection system and be familiar with their purpose and function

• interpret the symptoms of defects on the fuel system and draw conclusions

• explain what must be done after exchanging an fuel injector

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Overview of the two-module system – system with PCM and separate IDM

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CHT (Cylinder Head Temperature) sensor

1

Manifold absolute pressure sensor with integrated

T-MAP (Temperature And Manifold Absolute

IDM (BARO (Barometric Pressure) sensor

integrated in the control unit)

12

High pressure pump

13

Ignition lock14

PCM15

CAN (Controller Area Network)16

DLC (Data Link Connector)17

EGR valve18

Boost pressure control solenoid valve19

Intake manifold flap solenoid valve (85-kWFocus only)

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Overview of the single-module system – system with one PCM (IDM integrated in the PCM)

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Electrical turbocharger guide vane adjustmentactuator (emissions standard level IV only)18

EGR valve (not all versions)19

Boost pressure control solenoid valve20

Intake manifold flap solenoid valve (not allversions)

Characteristics

The following components originate from the Delphi

company:

• High pressure pump (with fuel metering valve and

fuel temperature sensor),

• Fuel rail (with fuel pressure sensor and pressure

limiting valve),

• Fuel injectors

The high pressure pump generates the fuel pressure

required and conveys it into the fuel rail Fuel metering

is performed by electrically actuating the fuel injectors

by the PCM or by the IDM

Special features

Solenoid valve-controlled fuel injectors are used in the

Delphi common rail system

In older systems a PCM and an IDM are used for engine

management

In more recent systems, the entire engine management

is carried out by a PCM

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Service instructions

Fuel injectors

A 16-digit identification number is engraved on every

fuel injector After replacing one or more fuel

injector(s), the identification number of the

corresponding fuel injector must be entered with the aid

of WDS

After a new software version has been loaded, it is also

necessary to enter the identification numbers of all fuel

injectors with the aid of WDS

Exact instructions on the input of identification numbers

can be found in the current Service Literature

Vehicles with coated diesel particulate filter

After replacing the PCM following a PCM crash

(communication with the PCM can no longer be

established using WDS) it may also be necessary to

replace the diesel particulate filter In this regard, always

refer to the instructions in the current Service Literature

After replacing the diesel particulate filter, using WDS

it is necessary to perform a supervisor parameter reset

as well as a reset of the parameters of the diesel

particulate filter differential pressure sensor in PCM In

this regard, always refer to the instructions in the current

Service Literature

After replacing the diesel particulate filter differential

pressure sensor it is necessary to reset the parameters

for the diesel particulate filter differential pressure

sensor In this regard, always refer to the instructions

in the current Service Literature

EEC V powertrain control module PCM (two-module system)

NOTE: If the PCM has been programmed with the latest

software version using WDS, ensure that the IDM isprogrammed with the latest software version as well Ifthis was not done automatically at the re-programmingstage, then it must be done manually immediately.Otherwise increased combustion noise, increased fuelconsumption and black smoke emissions may result

In the common rail injection system (two-modulesystem) an EEC V-PCM very similar to that in the VP30/VP 44 injection system is used

The EEC V-PCM calculates the overall injected fuelquantity and the injection timing and then sends thecalculated data to the IDM, which actuates the solenoidvalve-controlled fuel injectors accordingly

The control program (the software) is stored in amemory The execution of the program is carried out

Input signals from the sensors can have different forms.

Analog input signals

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Analog input signals can have any voltage value within

a given range Examples of analog input signals include:

• IAT (Intake Air Temperature),

• MAP,

• ECT (Engine Coolant Temperature)

As the microprocessor of the PCM can only process

digital signals, the analog input signals must first be

converted This is performed internally in the PCM in

an analog-to-digital converter (A/D converter)

Inductive input signals

Inductive input signals are pulsed signals that transmit

information about the engine speed and reference mark

Example:

• CKP sensor

The inductive signal is processed in an internal PCM

circuit Interference pulses are suppressed and the pulsed

signals are converted into digital square-wave signals

Digital input signals

Digital input signals have only two states:

• ON or OFF

Example of digital input signals:

– Speed sensor pulses of a Hall sensor (VSS (Vehicle

Variable switch-on timeb

Signal voltage1

Time2

The microprocessor transmits output signals to the

actuators via specific output stages The output signals

for the actuators can also have different forms:

• Switch signals (switch actuators on and off, such asthe A/C clutch),

• PWM (Pulse Width Modulation) signals PWMsignals are square-wave signals with constantfrequency, but variable switch-on time Using thesesignals electro-pneumatic transducers, for example,can be actuated at any location (for example theboost pressure control solenoid valve or EGRsolenoid valve)

The high-performance components for direct actuation

of the actuators are integrated in the PCM in such amanner that very good heat dissipation to the housing

is ensured

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Integrated diagnosis

In the case of sensor monitoring, the integrated

diagnostics are used to check if there is sufficient supply

to the sensors and whether their signal is in the

permissible range

Furthermore, it is possible to check whether a sensor

signal is within the permissible range via the control

program in the PCM

In the case of systems which work by means of a closed

control loop (the EGR system, for example), deviations

from a specific control range are also diagnosed

A signal path is deemed to be defective if a fault is

present beyond a predefined period The fault is then

stored in the fault memory of the PCM together with

freeze frame data (for example ECT, engine speed, etc.)

Back in working order recognition is implemented

for many of the faults This entails the signal path being

detected as intact over a defined period of time

Fault handling: If there are deviations from a

permissible set value for a sensor, the PCM switches to

a default value This process is used, for example, for

the following input signals:

• ECT, IAT,

• MAP, BARO,

• MAF

For some driving functions with higher priority (for

example APP sensor), there are substitute functions

which, for example, allow the vehicle to continue to be

driven to the next Authorized Ford Dealer

Diagnosis

The PCM performs self-monitoring to ensure correct

operation Malfunctions in the hardware or software of

the PCM are displayed by means of a DTC (Diagnostic

Trouble Code) Additional monitoring (see below) is

also performed

Reference voltage monitoring:

• In the case of reference voltage monitoring, so-calledcomparators compare the individual referencevoltages for the relevant sensors programmed in thePCM to check if they are within limits

• If a set reference voltage of 5 V falls to below 4.7

V, a fault is stored and the engine is stopped

EEPROM (Electrically Erasable Programmable Read Only Memory) monitoring:

• The engine adjustment data and freeze frame dataare stored in the EEPROM

• The freeze frame data forms part of the EOBD.Incorrect entries are detected appropriately andindicated by a DTC

Vehicles with EOBD

Reference voltage monitoring:

• Since the engine is stopped in the event of a fault,

this is non MIL active monitoring.

EEPROM (Electrically Erasable Programmable Read Only Memory) monitoring:

• Faults are MIL active, as the freeze frame data forms

part of the EOBD

IDM (two-module system)

NOTE: If the IDM has been programmed with the latest

software version using WDS, ensure that the PCM isprogrammed with the latest software version as well Ifthis was not done automatically at the re-programming

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stage, then it must be done manually immediately.

Otherwise increased combustion noise, increased fuel

consumption and black smoke emissions may result

NOTE: When re-programming the IDM, ensure that

the correction values for the fuel injectors are also

entered If this is not done, then it is not possible to start

the engine afterwards

The IDM is an intelligent fuel actuator

It processes information on the injected fuel quantity

and injection timing from the PCM and actuates the

fuel injectors accordingly

The following sensors are connected directly to the

via a separate cable This is because the engine speed signal has high priority, as it is used for calculating the

injected fuel quantity and the injection timing

The BARO sensor is integrated in the IDM and is used

to adapt the boost pressure and injected fuel quantity.However, the BARO sensor is only used in thecalculations if a variable geometry turbocharger isinstalled

Delphi PCM (single-module system)

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Ford diesel vehicles with Delphi common rail injection

systems are gradually being fitted with just one PCM

A separate IDM is no longer installed

The components and functions of the EEC V PCM and

the IDM are integrated in the Delphi PCM This is

referred to as a so-called single-module system.

The engine management and fuel injector actuation

strategies are identical with those of the engine

management system with the EEC V PCM and IDM,

the so-called two-module system.

Vehicles with coated diesel particulate filter

Note:

• After replacing the PCM following a PCM crash(communication with the PCM can no longer be

established using WDS) it may also be necessary to

replace the diesel particulate filter In this regard,always refer to the instructions in the current ServiceLiterature

Glow plug control

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