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Lots of cars today boast “direct injection,” so it seems commonplace, but that’s only a recent development. Getting the fuel into the cylinders of an internal-combustion engine takes some ingenuity, and it’s been a long road of “firsts” along the way between the late 19th century and the early 21st. The basic carburetor that served to blend fuel vapors with air and deliver the mixture to the intake manifold was one of the “firsts” on the 1886 car devised by Gottlieb Daimler and Wilhelm Maybach (some time before they joined forces with Karl Benz). Theirs is often regarded as the first car, and with refinements this carburetor system managed the task well enough for most cars for more than 80 years.

Fuel injection, which allows finer control of the mixture by spraying atomized fuel, was first managed by mechanical means and was a key element for the development of compression-ignition (diesel) engines in the 1920s. There, and in World War II aviation engines, the fuel was most often injected directly into the combustion chamber, known as “direct injection.” When injection started showing up in postwar gasoline production cars, there were dozens of variations but this direct-injection form was rare. One exception was the 1955 Mercedes-Benz 300SL that, like that era’s M-B racing cars, used a Bosch-developed mechanical direct-injection system. (Some credit a 1952 Goliath with a two-stroke engine that also employed Bosch direct injection, but Goliath was selling city cars in Europe only, and most of those cars had to have their injection replaced with carburetors because they failed.) The 300SL’s “first” is often qualified as the first “production sports car” with fuel injection.

It’s easier and cheaper to design and build injectors that don’t have to survive the hostile environment of a combustion chamber, so other pioneers in the late 1950s used systems that simply replaced the carburetor’s role in delivering fuel into the intake manifold. This generally meant a constant, though modulated, stream of fuel to mix with air drawn in through a throttle mechanism, hence “throttle-body fuel injection.” As emissions regulations and fuel efficiency became growing concerns, it became worthwhile to provide a separate injector for each cylinder, delivering a precisely metered dose of fuel only during the intake phase in that port, or “port fuel injection.” Another worthy refinement was to manage the fuel electronically. While American Motors built prototype Rambler Rebels in 1957 using a Bendix electronic system, it didn’t go into production, leaving “first” honors to Chrysler’s 1958 “Electrojector” system on that model year’s Chrysler 300D, De Soto Adventurer, Dodge D-500, and Plymouth Savoy. Only 35 buyers took the pricey option, and most had it replaced with the standard carburetor after it proved unreliable. So, perhaps the 1968 Volkswagen Type 3, which had the latest Bosch “D-Jetronic” system, could be considered the “first” successful electronic-injected car. Still, it delivered fuel to the manifold, not into the combustion chamber.

It wasn’t until 1996 that modern gasoline direct injection with electronic management appeared on the market. Mitsubishi gets the honors, first on the four-cylinder Galant sedan and on a V-6 the next year. The advantage: improved efficiency, yielding the magic trick of making more power while also getting better fuel economy. In the first five years, Mitsubishi built one-million cars with this GDI, well ahead of the rest of the industry. That Mitsubishi has all but disappeared from the U.S. automotive market suggests, again, that getting there first isn’t always a magic bullet for sales leadership. Or maybe that the company should have brought it here earlier instead of restricting initial sales to Asia and Europe. One challenge: New technology is generally more expensive, at least initially, and the advantage to the buyer isn’t always evident. Beginning in 2004, German luxury brands Audi and BMW did a better job of selling direct injection as an advantage in the United States.

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