[nota]

Originally Posted by henk4

was the Mercedes 220 SE (1959) mechanical?

Yes the Ponton (Roundy) used mechanical FI which in Mercedes passenger cars dates back to the 1955 300Sc (W188)

Bosch D-jet EFI dates from 1967, apparently debuting in the VW 411

From wiki

One of the first electronic fuel injection system was Electrojector, developed by the Bendix Corporation. In 1957, AMC was to offer a special edition Rambler Rebel with a 288 horsepower 327 in³ (5.4 L) engine optionally equipped with Electrojector. This was to have been the first production EFI engine, but Electrojector's teething problems meant only a few cars were so equipped, and all are thought to have been retrofitted with 4-barrel carburetors before they were first sold.

Chrysler offered Electrojector on the 1958 DeSoto Adventurer, arguably the first series-production car equipped with a throttle body EFI system, but the early electronic components weren't equal to the rigors of underhood service, and were too slow to keep up with the demands of "on the fly" engine control. Most vehicles originally so equipped were field-retrofitted with 4-barrel carburetors. The Electrojector patents were subsequently sold to Bosch.

Bosch developed an electronic fuel injection system, called D-Jetronic (D for Druck, the German word for pressure), which was first used on the VW 1600TL in 1967. This was a speed/density system, using engine speed and intake manifold air density to calculate "air mass" flow rate and thus fuel requirements. The system used all analog, discrete electronics, and an electro-mechanical pressure sensor. The sensor was susceptible to vibration and dirt. This system was adopted by VW, Mercedes-Benz, Porsche, Citroën, Saab and Volvo. Lucas licensed the system for production with Jaguar.

http://en.wikipedia.org/wiki/Fuel_injection