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Injection duration

Injection duration


Fuel mass/combustion

The fuel mass to be supplied to the engine per combustion has been calculated. The value is divided by 0.76 and is now converted to ml/combustion. The volume is accumulated for each combustion and the aggregate value is sent out on the bus. The main instrument unit uses the value for a correct fuel gauge display and the information display uses the value to calculate fuel consumption.

Injector opening time


Fuel volume/combustion is converted into injector opening duration, based on knowledge of the injector flow at 3 bar differential pressure.

Injection twice per combustion


Before the camshaft position has been detected, injection takes place semi-sequentially at 180° intervals. This means two cylinders at a time in the following order:


1. Cylinders 1 and 4.

2. Cylinders 2 and 3.


Each injector injects fuel once per crankshaft rotation and this means that the basic duration must be divided by two.

Needle lift delay


The time taken for the needle in the injector to lift is voltage-dependent. Depending on the battery voltage, the delay time is added to the basic duration.