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Injection duration

Injection duration


Fuel mass/combustion

The fuel mass to be injected into 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 value sent on the bus. The main instrument unit uses the value to display the fuel gauge correctly and the information display uses the value to calculate fuel consumption.

Injector opening duration


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

Injection twice/combustion


Before the camshaft position has been detected, injection takes place semi-sequentially at 120° intervals. This means two cylinders at a time in the following order:


1. Cylinders 1 and 4.

2. Cylinders 2 and 5.

3. Cylinders 3 and 6.


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.