There are several variations of the technology offering technological development and refinement. The volume of air taken in by the engine is measured to determine the amount of fuel to inject. K-Jetronic electronic fuel injection system pdf in the 1973. The final car to use K-Jetronic was the 1994 Porsche 911 Turbo 3.
Ku-Jetronic, the letter u denominating USA. Electronically controlled mechanical fuel injection. The system is based on the K-Jetronic mechanical system, with the addition of an electro-hydraulic actuator, essentially a fuel injector inline with the fuel return. With the electronics disconnected, this system will operate as a K-Jetronic system. Commonly known as ‘CIS-E’ in the USA. Despite physical similarity between L-Jetronic components and those produced under license by other manufacturers, the non-Bosch systems should not be called L-Jetronic, and the parts are usually incompatible.
The ECU was much cheaper to produce due to more modern components, and was more standardised than the L-Jetronic ECUs. As per L-Jetronic, a vane-type airflow sensor is used. Compared with L-Jetronic, the fuel injectors used by LE-Jetronic have a higher impedance. Three variants of LE-Jetronic exist: LE1, the initial version. ECU, which does not require the cold start injector and thermo time switch used by older systems. ECU with hybrid technology, integrated into the junction box of the mass airflow meter. Initially designed for the US market.