Early Otto cycle (4 cycle, spark ignition) engines had crude carburators. The development of compression ignition by Diesel led to fuel injection for compression ignition engines. Some companies experimented with injection for Otto cycle engines, some were even sold to the public. The advent of WW II led to major developments in aircraft use of fuel injection. After the war, fuel injection was occasionally offered by manufactures. In the early '60's Bendix developed (and patented !)the first electronically controlled fuel injection but was deemed not ready for consumer use. The gas crunch of the 70's and concerns about vehicle emissions forced the goverment to legislate better fuel efficiency and less emissions. The auto companies realized that carburators would not be sufficient to control the fuel for these precision requirements. Traditional engineering development dictates a gradual evolution to new technologies. It wasn't just the manufactures that had to make fuel injection, their dealers had to service it and someone had to make all these components.
In the late 70's Ford teamed with Bosch to develop fuel injection. One major problem was the electronics industry was barely ready to build the computers at a cost and capability to support automobile production. Ford decided to start simple and evolve. They developed their electronic fuel injection (EFI) system and called it Electronic Engine Control (EEC). The EEC would be developed in phases; EEC-I, EEC-II...etc (currently at EEC-V). Within each phase there would be development and evolution for several reasons, different platforms (Mustang V8, Escort, etc) and evolving emission requirements. The electronics industry would be evolving as well and in the future there would be more capability at a cheaper price.
|Year||Generation||Function||Speed||Memory||# I / O|
|'78||EEC-1||spark, EGR||4k bytes||12|
|'79||EEC-II||spark, EGR, fuel-feedback Carb||3 mhz||4k bytes||20|
|'80||EEC-III||spark, EGR, fuel-CFI||7.5 mhz||8k bytes||22|
|'83||EEC-IV||see table below||15 mhz||64k bytes||41|
The computer hardware design was planned to evolve slightly ahead of the software features implemented. This would give the software designers flexability to evolve with minimal hardware limitations. This way Ford could specify much fewer computer configurations to it's vendors (Intel, Toshiba) and only change the software for the different vehicles.
|hi speed digital output||10||5||8||10||9|
|low speed digital output||8||2||6||6||8|
|ROM (installed)||64k architecture||8k||16k||16k||16k|
Vehicle functions control by EEC-IV
|Manual shift trans light||x||x||x||x|
|Auto trans 4th gear lockup||x||x||x|
|Auto trans 2/3/4th gear lockup||x||x|
|Fuel flow DOL (not implemented on XR or SVO)||x||x||x||x|
|A/C cutoff @ WOT||x||x||x|
|Speed Control (XR is an external control system)||x||x|
|Component failure compensation (later called adaptive learning)||x||x|
|Engine Warning Light (not implemented on XR or SVO)||x|