HomeReviewsMediaBooksHow to Understand, Service, and Modify Ford Fuel Injection and Electronic Engine Control

Classics and Performance Logo

How to Understand, Repair, and Modify Ford Fuel Injection and Electronic Engine Control

Book Review

by Ryan King

U.S. Military Name Tapes Link

Let me begin this review by explaining that it evaluates two books. The reason I chose to review two books in one review is that they are two volumes of the same series.

How to Understand, Repair, and Modify Ford Fuel Injection and Electronic Engine Control covers Ford fuel injection from its inception as CFI (central fuel injection) in 1980 all the way up to SEFI (sequential electronic fuel injection, otherwise called SFI, sequential fuel injection) in 1993. The first book includes the years 1980-1987, the second from 1988-1993 — and they are very thorough.

The author, Charles O. Probst, did an excellent job of succinctly clarifying this complex subject. As the title of the books suggests, they teach you to understand, repair, and modify Ford fuel injection.

These books lay a sturdy foundation of theory that is built upon with the function of the fuel injection system, followed up with how to modify it, and finished with how to diagnose and repair it.

Now, it's important to note that if you are picking up these books to understand how the computer is programmed, it will only give you the basics of how it functions, not how to modify the program in any way. The reason — as it is explained in the books — is that Ford does not recommend modifying the computer in any way.

That doesn't mean they don't have any value for those more bent on reprogramming, especially if you don't have an intimate understanding of how the engine control system in a Ford works. In fact, I wouldn't consider touching any programming — whether the activity is considered legal or not — without having the information these books provide.

Let's take a look at what these books have to offer.

The Books

Chapter 1: Ford Electronic Engine Control — An Overview (Volumes 1 & 2)

As the title implies, this chapter provides an overview of Ford Electronic Engine Control, but it starts out with an overview of the book itself. It explains what the reader can expect to learn in each chapter and how each chapter builds on the information learned in previous chapters to create a complete picture of what Ford fuel injection is and does. Part two of this chapter covers fuel injection fundamentals which are contrasted with carburetors both for comparison and familiarity with the knowledge the reader might bring with them. Part three discusses the types of Ford fuel injection. Volume 1 covers CFI through SEFI more predominantly, while Volume 2 covers SEFI predominantly, which includes Ford EEC information as well as Mazda and Nissan systems (Ford fuel injection is based on Mazda fuel injection and the company has used all three systems in their cars). Part four covers the concept of total engine control, which is an important concept with fuel injection that didn't necessarily have to be considered with carbureted engines, but I think that once you start to think this way, you'll find that your approach to repair, modification, and design of carbureted engines will benefit from this approach as well. The final section covers applications — which include systems and vehicles. Both volumes have application tables that cover their respective years.

Chapter 2: Engine Control Fundamentals (Volumes 1 & 2)

The concept of engine control is far more holistic than the approach traditionally used with carburation. It takes into account and controls all engine running requirements, rather than dealing with them as separate factors (air/fuel, ignition, cooling, and so on), as carbureted engines traditionally do. This is important to understanding, repairing, and modifying Ford engine control. In both volumes, the introduction clearly lays out for you, what you will need to understand and what you will learn from this important foundation chapter. The focuses for the second section are the basic factors of engine control, which include air/fuel ratios and their effects on overall performance, spark timing and its effect on overall performance, and the impact of engine loads on both air/fuel requirements and spark timing. The third section covers control of intake air and begins to differ more between the two volumes as they deal with the different engine control systems used during their respective year ranges. The fourth part looks at air pressure and explains the different perspective required for understanding fuel injection versus carburetors. As far as I am concerned, I think that changing one's perspective from vacuum to absolute pressure as noted in these books also greatly helps when dealing with carbureted engines as well.

Chapter 3: Emission Control and Fuels (Volumes 1 & 2)

In Chapter 3, the author starts to link the chapters together, building on the foundation material learned in Chapter 2. While many people have taken the attitude that emission reduction and economy don't coincide with performance, Probst points out that that isn't true and explains why it isn't by expounding on what pollution is, how it is controlled, and what the trends for controlling that pollution looked like at the time of the writing of these books. Again, the first section is the introduction, which lays out what you can expect to learn from this chapter. In the second section he gets into the nitty-gritty of emission controls. You might think this is boring because it has nothing to do with performance, but I think when the section is over, you'll really have a greater appreciation for the concept of emission control, what it actually means (not just some components bolted on to your engine), and more importantly, how it can coincide with performance, as well as fuel economy. Because, as Probst goes into detail about, getting the best emissions not only hurts performance but fuel economy. However, done at the right times and in the right ways, many needs can be satisfied. Another important thing to note that the author stresses, in today's world, you aren't going to get away from either the emission rules or the NEED for emission control, so it's better to understand it so that you can work with it and get the performance you're after. The third section looks at fuels, which is to say regular gasoline, alternative fuels, and the way these fuels effect performance, emissions, and gas mileage. In Volume 1, section four concludes the chapter with a summary; in Volume 2 the summary is a part of section three. Both books have a list of emission related reference tables, which look at specific vehicles and emission limits, as well as other helpful reference material.

Chapter 4: Sensors — Determining Engine Operating Conditions (Volumes 1 & 2)

What purpose do sensors serve? What kinds of sensors are there? How do they work? These questions, their answers, and more are the focus of Chapter 4. As Probst states in the introduction, it's important to understand sensors to diagnose a problem with the way an engine is running as well as understanding what a computer is using to "make decisions" on how to operate the engine. In both volumes, section one of this chapter cover the introduction, sensor type, and switch type. Section two delves into the sensors that read engine RPM, crankshaft position, and cylinder identification. As you will discover, although it seems innocuous at first glance, cylinder identification is one of the most important signals the computer receives — without which, it would not be able to run the engine. In section three, Probst covers what sensors are used to measure engine load, which varies from car to car, engine to engine, and year to year and greatly effects the computer's capacity to adapt to changes in environment, engine condition (wear), and performance modifications. Section four looks at the sensors that read the intake air temperature. Section five deals with engine coolant temp sensors. Section six covers exhaust gas oxygen sensors, how they are designed, operate, and wear. Section seven deals with throttle position sensors and switches. Section eight looks at the types of knock sensors. Section nine differs from the other sections of this chapter in that it covers a wide range of sensors which make up the rest of those not mentioned up to this point. In Volume 1, section 10 is the chapter summary, but in Volume 2 it covers powertrain sensors. Volume 2 also has two more sections: 11 covers the chapter conclusion and 12 brushes over the Nissan Electronic Concentrated Engine Control System (NECCS) in the 1993 Mercury Villager.

Chapter 5: Control Module — Computing Engine Operation (Volumes 1 & 2)

To give an over-simplified answer, the control module (ECM, EEC, or ECU) processes signals, computes running requirements, and controls engine functions. The introduction (first section) covers what will be learned in the chapter. That includes how the control module collects data from the sensors, how it uses programming in the memory coupled with the data transmitted by the sensors to calculate signals sent to the actuators to control the engine function, and lastly, how it controls the various actuators. This section also introduces you to transmission control and the Powertrain Control Module (PCM) used in some cars of this vintage. In section two, both books look into input signal conditioning, that is, how the computer changes the raw signals sent from the sensors into signals it can understand. Section three covers the CPU or the central processing unit (chip) in the computer that actually processes the information and provides output information to the actuators. Section four shows that, like input signal conversion, it conditions output signals as well to control the actuators with the appropriate kind of electrical signal for each actuator. Adaptive strategy or a kind of AI is the focus of section five. Yes, your car can learn — about the environment, the engine, and even the way you drive. Section six covers the strategies the computer uses to deal with sensor and computer failures to keep your car running, if only until you can get it to a shop or back home. Section seven is different for Volumes 1 & 2. In Volume 1, it's the chapter conclusion. In Volume 2, it covers the MECS (Mazda Engine Control System) computer. In both volumes, each chapter concludes with valuable tables of computer information.

Chapter 6: Actuators — Implementing Control Strategies (Volumes 1 & 2)

Like hands and feet, actuators are what the EEC uses to accomplish its engine control tasks. In Chapter 6, the author delves into actuators, what they are, how they work, and how they are controlled. Section one is, of course, an introduction. Section two covers the actuators that control air and fuel. Section three deals with spark timing. Section four explains Idle Speed Control and Throttle Bypass Air metering. Section five focuses on emission control actuators. Section six, information signals, deals with the computer output signals to the driver and technician such as warning lights and trouble codes. Section seven covers relays and controls like those that transfer power to the fuel pump and control electric coolant fans. The last section, eight, differs between the two volumes. Volume 1 summarizes the chapter while Volume 2 covers Nissan engine management. In both volumes, Chapter 6 finishes with helpful tables such as control module outputs to actuators.

Chapter 7: Fuel Delivery Systems (Volumes 1 & 2)

While Chapters 4-6 cover the amount of fuel injected, Chapter 7 deals with how the fuel gets from the tank to the injectors. More than that, the author takes a close look at the importance of fuel line pressure, which is essential for proper control of the air/fuel ratio by the computer. As section one is again an introduction, I'll be skipping over that for section two, which explains the different types of fuel pumps as well as how the computer controls them. Pressure regulators are the subject of section three. Pressure regulators are the magic device that keeps fuel control constant at the injector, thus allowing the computer to precisely control the volume of fuel (relative to the volume of air) injected under a wide range of operating conditions. Section four delves into the importance of fuel filters in a fuel system and section five sheds light on the port injection fuel rail. In Volume 1, section six provides a summary. No such section exists in Volume 2.

Chapter 8: Strategies — Responding to Operating Conditions (Volumes 1 & 2)

This is it. If you've read the entire book up until this point, you've probably wondered how all these components work in concert to control the car. In this chapter Probst explains it all. Section one comes after the introduction in Chapter 8 and focuses on the warm cruise strategy, its sensors and actuators. Section two deals with the engine crank strategy, that is, how the computer recognizes and functions to start the engine. Section three covers cold start/warm-up which is different than engine crank in that the computer sees that the engine is running at this point. Cold driveaway is the subject of section four and covers conditions similar to driving with the choke on in a carbureted engine. Section five covers warm driveaway, which is similar to cold driveaway, but the engine is slightly warmer. Section six deals with part throttle acceleration, which is to say, light acceleration where the computer still uses signals from the closed-loop sensors to calculate the fuel volume. Full throttle acceleration (section seven) on the other hand causes the computer to go closed loop and ignore some sensors and dump in a pre-determined amount of fuel for maximum power output. Section eight takes a look at deceleration, which has some things in common with the warm idle strategy in section nine. Volume 1 has a tenth section that summarizes the chapter. Both volumes have useful tables dealing with the engine operating modes.

Chapter 9: Tuning for Performance and Economy (Volumes 1 & 2)

In the previous chapters, the author has explained how each component works and how they all work together, in Chapter 9, he takes the enthusiast to the next level: performance modifications. I'll let the author explain it in his own words from Volume 2:

"You know enough about the various ways that Ford systems meter fuel. We'll look at what Special Vehicle Operations (SVO), the factory performance group, and the aftermarket tuners, and parts suppliers offer you. We'll consider what features of the stock system you might have to give up. You'll know enough to ask questions and to understand the tradeoffs that usually accompany fuel-system modifications."

This, as well as legal and emission problems (at least for the time the book was written) are addressed in this chapter. Section one, of course, is the introduction, which the above paragraph was taken from. Section two takes a look at the history of Ford and its involvement in the performance arena. Section three deals with the legal issues enthusiasts face when modifying their car for increased performance. Section four helps you figure out what you intend to do with your car, such as street or track use as well as how modifications effect the emission legality of your vehicle. Section five focuses on the basics of engine performance and how they effect improvements. Section six runs the gamut of performance modifications from MAF conversions (Volume 1) to the installation of nitrous oxide and other power adders. Section seven delves into "questionable tricks" used by people who try to cheat the computer. Section eight in Volume 1 looks at the 2.3L four-cylinder engine and Volume 2 considers modifying Mazda Electronic Engine Control (MECS). Section nine in Volume 1 shows you some of the difficulties with modifying the Vane Air Flow Sensor in cars such as the '84-'86 SVO Mustang. In Volume 2, section nine draws the chapter to a conclusion, which Volume 1 does in section 10. Volume 1 also has a table for knock sensor applications.

Chapter 10: Diagnosis and Troubleshooting (Volumes 1 & 2)

Wait, this sounds boring!

No, it's actually extremely fascinating. Ok, maybe not as fascinating as fantasizing about how your car is going to demolish a supercar as soon as you add that supercharger, but it's actually quite interesting, and if you've read this far, this chapter makes a great deal of sense. As the author has mentioned, working on fuel injected cars isn't like working on carbureted ones. Without this chapter, you are really flying blind if you plan to apply any of the knowledge you've learned up to this point.

Section one, again introduces you to what you will be learning in the chapter. Section two, however is one of the most important in the whole book as it will teach you many of the finer details of diagnosis and troubleshooting which can be used on any part of any car during repair procedures. Section three looks into the concept of diagnostic routines — an important part of the diagnosis process. Section four looks at the concept of the quick test, which is checking the computer for trouble codes. Section five is the conclusion of the chapter. Each volume also has a table. Volume 1 shows Self Test connector locations and Volume 2 deals with SAE standardized terms for 1993 and later cars.

Chapter 11: Servicing (Volumes 1 & 2)

This chapter covers the actual hands-on techniques for troubleshooting problems from electrical to fuel systems. One more time, section one is the introduction, but in this chapter it takes a much more in-depth look at the process of electrical troubleshooting. Section two deals with the fuel system. Section three delves into air flow measurement. Section four explores troubleshooting the ignition system. Section five shows you how to check and set idle RPM. Section six deals with temperature sensors and in Volume 1, section seven is the conclusion. In both volumes the chapter ends with a host of helpful reference tables.

Chapter 12: Trouble Codes, Electrical Tests, and Wiring Diagrams (Volumes 1 & 2)

Along with the information learned in Chapters 10 and 11, chapter 12 will complete the diagnostic and troubleshooting picture for you. Section one, along with being the introduction, explains to you how to use trouble codes, electrical tests, and wiring diagrams. Section two deals with the actual trouble codes, themselves. Section three shows you how to test each component so that you are certain of where the failure that the computer detected really occurred. Section four provides a whole host of wiring diagrams for numerous Ford, Mercury, Lincoln, and Merkur vehicles. Although it seems like a bunch of codes after section two, be sure to read on through section three, it contains some very valuable information for working on these cars.

Chapter 13: Index (Volume 1); Appendices (Volume 2)

Chapter 14: Art Credits (Volume 1); Index (Volume 2)

Chapter 15: Glossary (Volume 1); Art Credits (Volume 2)

Chapter 16: Glossary (Volume 2)


Although the author, Charles O. Probst, is no longer with us, he's left behind two very informative volumes that concisely describe, in detail, the workings of the early electronic Ford fuel injection systems. I would highly recommend these books to anyone trying to work on or understand these complex systems. Not only do they provide a lot of information, but Probst does a fantastic job making the dry technical information palatable, if not entertaining in places. If you aren't already familiar with the concepts covered in these books, it would be difficult not to have a greater appreciation for fuel injection, engine management, and more once you've read either one or both.

•   •   •

For more information contact Bentley Publishers on the web at www.bentleypublishers.com, by phone 1.800.423.4595, or by email at www.bentleypublishers.com/feedback.htm.

U.S. Military Name Tapes Link