Half Sequential Fuel Injection

Another new feature of the Motronic M1.1 is Half Sequential Fuel Injection. In the previous system the injectors opened at the same time on every complete crankshaft revolution, i.e. two injections per each working cycle (7200).





In the M1.1 system the injectors are divided into two groups according to the firing order: Group 1 consists of the injectors for cylinders nos. 1, 5 and 3; Group 2 consists of the injectors on cylinder nos. 6, 4 and 2. The control unit gets the injector group identification information from an induction transmitter on the ignition lead of cylinder no. 6.

Given the same operating circumstances as the previous Motronic system, the M1.1 will inject fuel to the respective group of three cylinders (depending on firing order sequence) at one half of the working cycle (360°).

The duration of the injection period is calculated in relation to the intake airflow signal (load), the engine speed signal and the various correction factors. During acceleration there are additional injections to ensure immediate response and performance.

The layout of half sequential fuel injection provides emergency running abilities in the event of a group failure.