31S07T0 engine peformance theory and operation 2003

FCS-14568-REF
Updated January, 2006

Ford Customer Service Division
Technical Training



IMPORTANT SAFETY NOTICE
Appropriate service methods and proper repair procedures are essential for the safe, reliable operation of all motor vehicles,
as well as the personal safety of the individual doing the work. This manual provides general directions for accomplishing
service and repair work with tested, effective techniques. Following them will help assure reliability.
There are numerous variations in procedures, techniques, tools and parts for servicing vehicles, as well as in the skill of the
individual doing the work. This manual cannot possibly anticipate all such variations and provide advice or cautions as to
each. Accordingly, anyone who departs from instructions provided in this manual must first establish that he compromises
neither his personal safety nor the vehicle integrity by his choice of methods, tools or parts.
As you read through the procedures, you will come across NOTES, CAUTIONS, and WARNINGS. Each one is there for a
specific purpose. NOTES give you added information that will help you to complete a particular procedure. CAUTIONS are
given to prevent you from making an error that could damage the vehicle. WARNINGS remind you to be especially careful
in those areas where carelessness can cause personal injury. The following list contains some general WARNINGS that
you should follow when you work on a vehicle.

•
•

Always wear safety glasses for eye protection.

•
•

•

To prevent serious burns, avoid contact with hot metal
parts such as the radiator, exhaust manifold, tail pipe,
catalytic converter and muffler.

Be sure that the ignition switch is always in the OFF
position, unless otherwise required by the procedure.

•
•

Do not smoke while working on the vehicle.

Set the parking brake when working on the vehicle. If you
have an automatic transmission, set it in PARK unless
instructed otherwise for a specific service operation. If
you have a manual transmission it should be in REVERSE (engine OFF) or NEUTRAL (engine ON) unless
instructed otherwise for a specific service operation.

•

Keep hands and other objects clear of the radiator fan
blades. Electric cooling fans can start to operate at any
time by an increase in underhood temperatures, even
though the ignition is in the OFF position. Therefore, care
should be taken to ensure that the electric cooling fan is
completely disconnected when working under the hood.

Use safety stands whenever a procedure requires you to
be under the vehicle.

•

Operate the engine only in a well-ventilated area to avoid
the danger of carbon monoxide.

•

Keep yourself and your clothing away from moving parts
when the engine is running, especially the fan and belts.

To avoid injury, always remove rings, watches, loose
hanging jewelry, and loose clothing before beginning to
work on a vehicle. Tie long hair securely behind your
head.

The recommendations and suggestions contained in this manual are made to assist the dealer in improving his dealership parts
and/or service department operations. These recommendations and suggestions do not supersede or override the provisions of
the Warranty and Policy Manual, and in any cases where there may be a conflict, the provisions of the Warranty and Policy Manual
shall govern.
The descriptions, testing procedures, and specifications in this handbook were in effect at the time the handbook was
approved for printing. Ford Motor Company reserves the right to discontinue models at any time, or change specifications,
design, or testing procedures without notice and without incurring obligation. Any reference to brand names in this manual
is intended merely as an example of the types of tools, lubricants, materials, etc. recommended for use. Equivalents, if
available, may be used. The right is reserved to make changes at any time without notice.
WARNING: MANY BRAKE LININGS CONTAIN ASBESTOS FIBERS. WHEN WORKING ON BRAKE COMPONENTS, AVOID
BREATHING THE DUST. BREATHING THE ASBESTOS DUST CAN CAUSE ASBESTOSIS AND CANCER.
Breathing asbestos dust is harmful to your health.
Dust and dirt present on car wheel brake and clutch assemblies may contain asbestos fibers that are hazardous to your health
when made airborne by cleaning with compressed air or by dry brushing.

Wheel brake assemblies and clutch facings should be cleaned using a vacuum cleaner recommended for use with asbestos fibers.
Dust and dirt should be disposed of in a manner that prevents dust exposure, such as sealed bags. The bag must be labeled per
OSHA instructions and the trash hauler notified as to the contents of the bag.
If a vacuum bag suitable for asbestos is not available, cleaning should be done wet. If dust generation is still possible, technicians
should wear government approved toxic dust purifying respirators.
OSHA requires areas where asbestos dust generation is possible to be isolated and posted with warning signs. Only technicians
concerned with performing brake or clutch service should be present in the area.
Copyright © 2003 Ford Motor Company

Produced and Coordinated by
Technical Support Operations
Ford Customer Service Division
September, 2003


CUSTOMER EXPECTATIONS
Customer Expectations: Service

1. Make it convenient to have my
vehicle serviced at your dealership.

2. The Service Advisor should

5. Provide me with a clear and thorough
explanation of the service performed.

6. Call me within a reasonable amount of

demonstrate a genuine concern for
my service needs.

time after my service visit to ensure that
I'm completely satisfied.

3. Fix it right the first time.
4. Complete servicing my vehicle in a

7. Be responsive to questions or concerns
I bring to your attention.

timely and professional manner.
Expectation 3
“Fix It Right The First Time, on Time.”
Both service advisors and technicians are important players when it comes to Expectation
#3.
Why
Customers tell us “Fixing It Right The First Time, on Time” is one of the reasons they
would decide to return to a dealer to buy a vehicle and get their vehicles serviced.
Technician Training
It is our goal to help the technician acquire all of the skills and knowledge necessary to
“Fix It Right The First Time, on Time.” We refer to this as “competency.”
Technician’s Role
Acquire the skills and knowledge for competency in your specialty via:
STST
New Model
– Self Study
– Self Study
– FordStar Broadcasts
– FordStar Broadcasts
– Ford Multimedia Training (FMT)

– Instructor Led
– Instructor Led
The Benefits
The successful implementation of expectations means:
– Satisfied customers
– Repeat vehicle sales
– Repeat service sales
– Recognition that Ford and Lincoln/Mercury technicians are “the Best in the
Business”


TABLE OF CONTENTS
INTRODUCTION
Engine Performance Curriculum Goals ..................................................................................... Intro-1
Organization of the Student Information Book ......................................................................... Intro-3
Day One Agenda ........................................................................................................................ Intro-6
Day Two Agenda ....................................................................................................................... Intro-9
IGNITION REVIEW
Student’s Objective .......................................................................................................................... 1-1
Content ............................................................................................................................................ 1-1
Basic Ignition System Operation ..................................................................................................... 1-2
Voltage and Coils ............................................................................................................................. 1-3
Ignition Timing .............................................................................................................................. 1-13
Ignition Requirements and Operating Conditions ......................................................................... 1-17
Distributorless Ignition Systems .................................................................................................... 1-23
Coil-On-Plug Ignition System ....................................................................................................... 1-41
FUEL/AIR INLET REVIEW
Student’s Objective .......................................................................................................................... 2-1
Content ............................................................................................................................................ 2-1
Fuel and Air Inlet Systems .............................................................................................................. 2-2

Air Intake System ............................................................................................................................ 2-9
Air Measurement Systems ............................................................................................................. 2-23
Fuel System ................................................................................................................................... 2-27
Fuel Control ................................................................................................................................... 2-41
EXHAUST/EMISSION REVIEW
Student’s Objective .......................................................................................................................... 3-1
Content ............................................................................................................................................ 3-1
Exhaust/Emission System ............................................................................................................... 3-2
Positive Crankcase Ventilation (PCV) ............................................................................................. 3-5
Evaporative Emission (EVAP) System .......................................................................................... 3-13
Exhaust Gas Recirculation (EGR) ................................................................................................. 3-27
Secondary Air Injection Reaction (AIR) ....................................................................................... 3-39
Catalytic Converter (CAT) ............................................................................................................. 3-45
OBDII ............................................................................................................................................ 3-53
WORKSHEETS
DAY ONE
Worksheet 1 Secondary Concern ................................................................................. Worksheets-1A
Worksheet 2 Cop Coil Concern ................................................................................... Worksheets-2A
Worksheet 3 Air Leak .................................................................................................. Worksheets-3A
Worksheet 4 Injector Concern ..................................................................................... Worksheets-4A
DAY TWO
Worksheet 1 Fuel Pressure...........................................................................................
Worksheet 2 Drive Session ..........................................................................................
Worksheet 3 Vacuum Leak ..........................................................................................
Worksheet 4 Electronic Publications Navigation ........................................................

Theory and Operation

July, 2001

Worksheets-1A
Worksheets-2A
Worksheets-3A
Worksheets-4A

i


TABLE OF CONTENTS
NOTES

ii

July, 2001

Theory and Operation


INTRODUCTION
ENGINE PERFORMANCE CURRICULUM GOALS
The goal of the Engine Performance Curriculum is to provide you with necessary training to “Fix it right the first
time.” This Engine Performance Theory and Operation classroom course provides you with hands-on practice as
it relates to the theory and operation, as well as, the relationships among engine performance systems and system
types.

Planned Training Pathway
Ford Motor Company has identified the skills and knowledge necessary to meet the Engine Performance
Curriculum goals. The Planned Training Pathway is a sequence of courses that are designed to provide you with
these skills and knowledge.

Engine Performance Curriculum Overview
The Engine Performance Curriculum consists of all of the following types of courses:
Web-based – These courses are self-paced. The technician is responsible for learning the material on his/her own
time. The courses are posted on the Internet and technicians are given the appropriate access codes.
Ford Multimedia Training (FMT) – These courses are also self-paced. The multimedia courses are highly
interactive and allow the technician to simulate hands-on activities.
Classroom – The classroom courses allow for application of the skills and knowledge learned in the prerequisite
courses through hands-on, real-world scenarios.
FORDSTAR – These courses are instructor-led, interactive, live broadcasts presented over the FORDSTAR
Distance Learning Network. The instructor presents information, asks questions, and interacts with the
technicians. Demonstrations and video clips are used to present material.

Theory and Operation

July, 2001

Intro-1


INTRODUCTION
How to Complete the Curriculum
To successfully complete the Engine Performance Curriculum, you must take the following sequence of courses:

Ignition System Theory and Operation –
Course Code 31S01W0
Fuel and Air Inlet System Theory and Operation –
Course Code 31S02W0
Exhaust/Emission System Theory and Operation –
Course Code 31S03W0
Fuel Air Ignition and Emission System

Relationships – Course Code 31S04W0
OBDII Monitors –
Course Code 31S05W0
Engine Performance Theory and Operation –
Course Code 31S07T0
Driveability Diagnostic Process –
Course Code 31S06W0
Driveability Diagnostic Routines –
Course Code 31S08W0
Engine Performance Diagnosis and Testing –
Course Code 31S10T0
Advanced Driveability Diagnosis and Testing –
Course Code 31S09M0
Advanced Engine Performance
Diagnosis and Testing – Course Code 31S12T0

Intro-2

July, 2001

Theory and Operation


INTRODUCTION
ORGANIZATION OF THE STUDENT INFORMATION BOOK
The student information book is divided into three sections that include the following information:
l

Introduction
– Describes the STST Engine Performance Curriculum and objectives of the Theory and Operation Classroom

– Reviews the requirements for course completion
– Includes the morning and afternoon flow charts and agenda for both Day One and Day Two

l

Review Lessons 1-3
– Each Lesson starts with the Student Objectives and a content outline
– Workbook pages contain graphics and review material from previous WBT courses

l

Day One and Day Two Worksheets
– Contains student worksheets and review questions

Target Audience
The Engine Performance Theory and Operation classroom is designed for entry-level Ford Motor Company
engine performance technicians.

Course Length
This is a two-day course.

Course Prerequisites
Before you enroll in this course, you must meet the following prerequisites:
l

Basic Electrical Part 3 – 34S03T0 (Classroom)

l

Electronics Part 3 – 34S06T0 (Classroom)

l

WBT Courses:
– Air, Fuel, Ignition, and Exhaust Systems Relationships – 31S04W0
– OBDII Monitors – 31S05W0

Theory and Operation

July, 2001

Intro-3


INTRODUCTION
Course Description
This is a two-day hands-on course designed to provide you with maximum hands-on application of Engine
Performance systems theory and operation as well as the relationships between systems and system types during
normal operating conditions. The first day is a combination of instructor review and lecture, instructor-led
demonstrations, and hands-on workstations. The second day is a continuation of the hands-on workstations and
culminates in the final exam.

Course Objectives
Upon completion of the Engine Performance Theory and Operation classroom, you will be able to:
l

Review Critical Concepts from the prerequisite WBT courses
– Explain the critical concepts of Ignition Systems theory and operations
– Explain the critical concepts of Fuel and Air Inlet System theory operations
– Explain the critical concepts of Exhaust/Emissions Systems theory operations

– Explain the relationships between the Air, Fuel, Ignition, and Exhaust/Emissions systems
– Explain the purpose and function of the OBD II monitors

l

Locate appropriate information in the Ford Electronic Publications System

l

Perform and interpret measurement results using specific diagnostic tools
– Perform and interpret measurement results for normal systems operations
– Perform measurements on system operations under certain conditions
– Select PIDs
– Monitor systems operations using PID values
– Perform Spark Duration and Peak kV tests
– Explain the effect of certain conditions on systems operations
– Explain how the systems compensate for certain conditions

Intro-4

July, 2001

Theory and Operation


INTRODUCTION
Course Structure
The Engine Performance Theory and Operation classroom course has the following structure:
l

Review – You will be asked to complete review questions that address content covered in the prerequisite
courses. Afterwards, the instructor will direct a review/lecture that includes critical concepts necessary for
understanding the theory and operation of engine performance systems. The review questions and individual
student responses to these questions can be used as a guide to conduct this lecture. In this way, the instructor
can also address any “often-missed” review questions.

l

Instructor Demonstration – The instructor will demonstrate WDS as it pertains to the workstations.

l

Workstations – The instructor will present the concepts that are critical to successfully completing the
workstations. You will participate in two on-vehicle workstations, and two electronic resource activities each
day.

l

Worksheets – All workstations have an accompanying worksheet designed to complement the hands-on
activities. All workstations and worksheets are identified by number.

l

Evaluation – At the end of the two-day course, the instructor will ask you to complete a final written test,
which includes a WDS recorded session where you are asked to evaluate data, and a course evaluation.

Evaluation Strategies
The final exam is given in the afternoon of Day Two. It contains written questions to evaluate your skill and
knowledge and a WDS recorded session.
You will complete the written evaluations at your seat. The questions focus on areas identified during the two-day

classroom session and require critical thinking skills to solve problems. You must correctly answer 80% of the
written questions in order to pass.
You may use all of the reference material available to you in the classroom, including workshop manuals and the
student information book. However, the sharing of answers with the other technicians will not be permitted.

Theory and Operation

July, 2001

Intro-5


INTRODUCTION
DAY ONE AGENDA
The agenda for Day One is as follows:

TASK

START
TASK

FINISH
TASK

Welcome/Course Overview

8:30 a.m.

9:00 a.m.

Review questions – 41 questions

9:00 a.m.

9:30 a.m.

Break

9:30 a.m.

9:45 a.m.

Review of critical concepts as determined by results of review questions

9:45 a.m.

11:45 a.m.

Description of Day One workstations

11:45 a.m.

12:15 p.m.

Lunch

12:15 p.m.

1:15 p.m.

Instructor demo of WDS navigation

1:15 p.m.

1:30 p.m.

Workstation #1 – Worksheet 1 – Secondary Ignition (on-vehicle)

1:30 p.m.

2:00 p.m.

Workstation #2 – Worksheet 2 – COP Fault (recorded WDS session)

2:00 p.m.

2:30 p.m.

Break

2:30 p.m.

2:45 p.m.

Workstation #3 – Worksheet 3 – Air Leak (on-vehicle)

2:45 p.m.

3:15 p.m.

Workstation #4 – Worksheet 4 – Injector Fault (recorded WDS session)

3:15 p.m.

3:45 p.m.

Review four (4) worksheets from Day One rotation

3:45 p.m.

4:45 p.m.

END OF DAY ONE

Intro-6

4:45 p.m.

July, 2001

Theory and Operation


INTRODUCTION
Day One Flowchart

Welcome
and
Course Overview

Review
Questions

Demonstration of WDS Navigation:
• Accessing previous sessions
• DataLogger
• Ignition test

Lunch

Day One
Workstations

Theory and Operation

Debrief of Day One
Workstation
Rotations

July, 2001

Break

• Review of critical concepts as
determined by review questions
• Description of Day One
Workstations

End

Intro-7


INTRODUCTION
Day One – Afternoon Workstation Rotations

Intro-8

Team 1 –
Worksheet 1
Secondary
Ignition
On-Vehicle

Team 1 –
Worksheet 2
COP Fault
Recorded
WDS Session

Team 1 –
Worksheet 3
Air Leak
On-Vehicle

Team 1 –
Worksheet 4
Injector Fault
Recorded
WDS Session

Team 2 –
Worksheet 2
COP Fault
Recorded
WDS Session

Team 2 –
Worksheet 3
Air Leak
On-Vehicle

Team 2 –
Worksheet 4
Injector Fault
Recorded
WDS Session

Team 2 –
Worksheet 1
Secondary
Ignition
On-Vehicle

Team 3 –
Worksheet 3
Air Leak
On-Vehicle

Team 3 –

Worksheet 4
Injector Fault
Recorded
WDS Session

Team 3 –
Worksheet 1
Secondary
Ignition
On-Vehicle

Team 3 –
Worksheet 2
COP Fault
Recorded
WDS Session

Team 4 –
Worksheet 4
Injector Fault
Recorded
WDS Session

Team 4 –
Worksheet 1
Secondary
Ignition
On-Vehicle

Team 4 –

Worksheet 2
COP Fault
Recorded
WDS Session

Team 4 –
Worksheet 3
Air Leak
On-Vehicle

July, 2001

Theory and Operation


INTRODUCTION
DAY TWO AGENDA
The agenda for Day Two is as follows:

TASK

START
TASK

FINISH
TASK

Description of Day Two Workstations

8:30 a.m.

9:00 a.m.

Workstation #1 – Worksheet 1 – Fuel Pressure (on-vehicle)

9:00 a.m.

9:30 a.m.

Workstation #2 – Worksheet 2 – Drive Recording (recorded WDS session)

9:30 a.m.

10:00 a.m.

Break

10:00 a.m.

10:15 a.m.

Workstation #3 – Worksheet 3 – Vacuum Leak (on-vehicle)

10:15 a.m.

10:45 a.m.

Workstation #4 – Worksheet 4 – Electronic Publications Navigation (PC)

10:45 a.m.

11:15 a.m.

Review four (4) worksheets from Day Two rotation

11:15 a.m.

12:15 p.m.

Lunch

12:15 p.m.

1:15 p.m.

1:15 p.m.

4:45 p.m.

Post-Test
END OF DAY TWO

Theory and Operation

4:45 p.m.

July, 2001

Intro-9

INTRODUCTION
Day Two Flowchart

Description of
Day Two
Workstations

Post-Test

Day Two
Workstation
Rotations

Lunch

Break

Debrief of Day Two
Workstation
Rotations

End

Intro-10

July, 2001

Theory and Operation

INTRODUCTION
Day Two – Morning Workstation Rotations

Team 1 –
Worksheet 1
Fuel
Pressure
On-Vehicle

Team 1 –
Worksheet 2
Drive
Recording
WDS Session

Team 1 –
Worksheet 3
Vacuum
Leak
On-Vehicle

Team 1 –
Worksheet 4
Elect. Pubs.
Navigation
(PC)

Team 2 –
Worksheet 2

Drive
Recording
WDS Session

Team 2 –
Worksheet 3
Vacuum
Leak
On-Vehicle

Team 2 –
Worksheet 4
Elect. Pubs.
Navigation
(PC)

Team 2 –
Worksheet 1
Fuel
Pressure
On-Vehicle

Team 3 –
Worksheet 3
Vacuum
Leak
On-Vehicle

Team 3 –
Worksheet 4

Elect. Pubs.
Navigation
(PC)

Team 3 –
Worksheet 1
Fuel
Pressure
On-Vehicle

Team 3 –
Worksheet 2
Drive
Recording
WDS Session

Team 4 –
Worksheet 4
Elect. Pubs.
Navigation
(PC)

Team 4 –
Worksheet 1
Fuel
Pressure
On-Vehicle

Team 4 –
Worksheet 2

Drive
Recording
WDS Session

Team 4 –
Worksheet 3
Vacuum
Leak
On-Vehicle

Theory and Operation

July, 2001

Intro-11


INTRODUCTION
NOTES

Intro-12

July, 2001

Theory and Operation


DAY ONE

IGNITION REVIEW

STUDENT’S OBJECTIVE
l

CONTENT

Review the critical concepts of the ignition system
theory and operation.

Theory and Operation

l

Basic Ignition System Operation

l

Voltage and Coils

l

Ignition Timing

l

Ignition Requirements and Operating Conditions

l

Distributorless Ignition Systems

l

Coil-On-Plug Ignition Systems

July, 2001

1-1


IGNITION REVIEW

DAY ONE

BASIC IGNITION SYSTEM OPERATION

Basic Ignition System
The purpose of the ignition system is to provide a spark to the correct cylinder at the correct time to ignite the air/
fuel mixture. The cylinders must fire in the proper order and at the precise time, depending on engine speed and
load. Proper ignition is critical to engine performance, fuel economy, and exhaust emissions. Improper ignition
can cause driveability symptoms and create excessive emissions.
All ignition systems operate in a similar manner. Current flow in the coil primary circuit is interrupted to produce
a high voltage in the secondary coil circuit, which fires the spark plug. The differences are in how the ignition
system controls primary circuit current flow and how the secondary high voltage is distributed to the spark plugs.

1-2

July, 2001

Theory and Operation

DAY ONE

IGNITION REVIEW

VOLTAGE AND COILS

kV
1

3
2

EP1002 -A/VF

Ignition Coil
Item

Description

1

Ignition coil

2

Secondary windings

3

Primary windings

The ignition coil is the component that converts low voltage into the required high voltage. This high voltage is
used to create a spark in the combustion chamber. Typically, ignition coils are capable of producing greater
than 25kV.
All ignition coils have a primary and secondary winding. The secondary winding contains many times more
windings than the primary winding.

Theory and Operation

July, 2001

1-3


IGNITION REVIEW

DAY ONE

Ignition Primary Circuit
The ignition primary circuit is the low voltage portion of the ignition system. The function of the primary circuit
is to energize the ignition coil in order to produce the high voltage required in the secondary circuit. The primary
circuit consists of the supply voltage circuit and the ground (coil -) circuit.
Supply Voltage Circuit

1
2

3

EP1003-A/VF

Supply Voltage Circuit
Item

Description

1

Battery

2

Ignition switch

3

Ignition coil

When the ignition switch is in the ON position, battery voltage is applied to the primary winding of the ignition
coil.

1-4

July, 2001

Theory and Operation

DAY ONE

IGNITION REVIEW

Ground Circuit

Ground Circuit
Item

Description

Item

Description

1

Ignition switch

4

ICM

2

Ignition coil

5

PCM

3

Solid-state switch

A solid-state switch provides the ground circuit for the coil primary winding. When the switch is closed, current
flows through the ignition supply circuit, the coil primary winding, and the ground circuit.
Before the introduction of electronic ignition systems, the ground circuit for the coil primary winding was
provided and interrupted by a set of breaker points.

Theory and Operation

July, 2001

1-5


IGNITION REVIEW

DAY ONE

Primary Current Flow

1

2

3
4
EP1005-A/VF

Coil Charging
Item

Description

Item

Description

1

Primary coil winding

3

Solid-state switch

2

ICM

4

Magnetic field

Current flow through the primary winding creates a magnetic field around the windings. The strength of the
magnetic field depends on the amount of current flowing through the primary winding.
When the maximum primary current flow is obtained (coil saturation), the magnetic field is at maximum
strength. It takes approximately 1.5 to 4.0 milliseconds (ms), depending on coil type, for most coils to reach

target current.

1-6

July, 2001

Theory and Operation


DAY ONE

IGNITION REVIEW

Magnetic Field Collapse/Induction

1

2

3
4
5
EP1006-A/VF

Magnetic Field Collapse/Induction
Item

Description

Item

Description

1

Primary coil winding

4

Max. allowed primary current

2

ICM

5

Coil OFF

3

Solid-state switch

When the solid-state switch opens, primary current flow stops. This causes the magnetic lines of force around the
primary winding to collapse. When the magnetic field collapses, the lines of magnetic force move very quickly to
the center and a higher voltage is induced due to the greater number of secondary windings, and the coil fires.
Dwell
Dwell is the amount of time that current is flowing through the primary circuit (coil ON time).

Theory and Operation

July, 2001

1-7