L-/LE-JETRONIC injection device (BMW 3 Series E30)

The L-/LE-Jetronic injection device is an electronic injection device for a petrol engine that provides pulsed fuel supply into the intake manifold in front of the intake valves.

Fuel is supplied by an electric fuel pump from the fuel tank through the fuel filter to the distribution pipe and then to the injectors. A pressure regulator in the distribution pipe ensures constant pressure. A vibration damper reduces pressure fluctuations in the fuel return channel.

Air is sucked in by the engine through the air filter and the air intake pipe and is measured by the air flow meter. The air flow meter housing contains a flap that is deflected by the air passing through it at a certain angle. The angular position of the flap serves as a measure of the amount of air passing through. Information about this amount is transmitted to the control unit from the potentiometer.

Stabilization of the engine speed during the warm-up process is ensured by an additional air damper.

The throttle switch is located directly on its axis. It sends signals to the control unit about the throttle position in idle and full load mode. Thanks to this, control in forced running mode occurs first of all; as long as the throttle switch contact is closed and the engine speed is greater than 1200 rpm, the fuel supply to the engine is blocked.

The control unit is located behind the trim in the glove compartment.