Injection device L-/LE-/LU-JETRONIC, MOTRONIC (BMW 3 Series E30)

Depending on the model, BMW injection engines are equipped with fuel injection variants based on the L-Jetronic system, such as LE-Jetronic, LU-Jetronic or Motronic. Motronic is also called the digital engine management system DME. The L-Jetronic system has been installed on the 318i since September 1983. Until August 1983, the K-Jetronic injection system was installed on the 318i, which is fundamentally different from the L-Jetronic.

The control unit regulates the injection time and thus the amount of fuel injected according to the measured air mass. More fuel is injected when the injector is opened longer. Additional sensing elements and sensors ensure that the correct amount of fuel is supplied even in extreme driving situations.

The starting valve injects additional fuel into the intake manifold to facilitate engine starting.

The thermal time switch determines the duration of injection by the injector when starting a cold engine.