Tag: fuel injection

Electronic Fuel Injection Article Thesis Statement

Because it grew more elaborate than I had initially envisioned, I realize the original object of the recent article on the Bendix Electrojector and Bosch D-Jetronic systems may have suffered a bit of forest-for-the-trees syndrome, so it might be worthwhile for me to clearly restate the thesis.

The principal object of the article was to investigate the commonly held assumption that Bendix simply sold the rights to the Electrojector system to Bosch, which then tidied it up and put it back into production as D-Jetronic. After delving into this contention at some length, my conclusion is that this isn’t really accurate. Rather, the appearance of the Bendix system in the fifties (of which Bosch was definitely aware) inspired Bosch to launch its own electronically controlled gasoline injection (ECGI) development program, which followed along some similar lines. This project probably would have ended up on the shelf due to lack of automaker interest had developments in California tailpipe emissions standards not forced the issue in 1964. By that time, Bendix, which had mostly shelved its fuel injection program after the failure of the Electrojector in 1957–1958, had secured worldwide patent protection covering many fundamental aspects of electronic fuel injection with timed speed-density metering. So, in order to put D-Jetronic in production for Volkswagen, Bosch was obliged to obtain a license from Bendix to use technology covered by those patents. Bendix retained control of the underlying IP, and subsequently also negotiated a reciprocal agreement for access to Bosch ECGI patents for use in the Bendix electronic fuel injection system subsequently offered by Cadillac and Chevrolet in the mid-seventies.

Neither Bendix nor Bosch invented the basic concept of timed low-pressure/common-rail electronic fuel injection with solenoid-controlled injection valves, which had been tried (albeit without commercial success) in the thirties. However, applying that concept with a metering system capable of handling all the aspects of passenger car operation was a challenging prospect, which wasn’t really completely addressed until the advent of the later Bosch L-Jetronic system (with mass airflow metering) and the addition of oxygen sensor feedback controls.

Electrojector and D-Jetronic: Early Electronic Fuel Injection

Once considered exotic technology, electronic fuel injection has been around a surprisingly long time. In this installment of Ate Up With Motor, we review the origins of EFI and examine the relationship between the pioneering Bendix Electrojector, Bosch D-Jetronic, and the second-generation Bendix system that introduced GM to electronic injection in the 1970s — a complicated web of technology, business, and politics.

Seville and "Fuel Injection" badges on the right front fender of a Naples Yellow 1977 Cadillac Seville sedan (Aaron Severson)

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