Engine details Part 1: EFI of 1974 Datsun 160J SSS KP710 Violet Turbo

In my previous postings, I have mentioned the electronic fuel injection system of the 1974 Datsun Violet Turbo being a Bosch D-Jetronic hybrid. The system was developed in the 1960s. It was probably the earliest of the "speed-density" efi system.

Figure 1
Fuel pressure regulator used to set constant fuel pressure.

Datsun/Nissan specifically calls their system the ECGI system. ECGI stands for "Electronic Control Gasoline Injection" resounding of US influence in the naming conventions, in my opinion, that is :-). This system was similarly employed in their first generation(smooth valve cover) normally aspirated LZs of the early 70s as well as the 240Zs with cross-flow LY heads.

The original D-jetronic system runs a constant fuel pressure versus the variable pressure system of today. It was possibly last used in mass production in 1976.


Its main measure of airflow comes from a manifold absolute pressure sensor.

Figure 2
MAP sensor using an inductive element coupled to manifold vacuum.

The hybrid portion mentioned earlier comes from a panel control box fitted on the passenger side with five knobs. Details of the five knobs can be found in the ECGI documentation portion which will be mentioned later.

Figure 3
ECGI Control box with five knobs. Details in figure 6.

A view of the Datsun/Nissan ECGI system ecu and control box is shown in figure 4.

Figure 4
ECGI ecu and control box with wiring.

Finer details of the five knobs...figure 5

Figure 5
Five knobs on control box.

Function of control box five knobs, see figure 6.

Figure 6
ECGI Notes on the control box settings.

More to come...cheers