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Fuel calculation

Fuel calculation

The amount of fuel allowed for starting the engine is based on the engine temperature and engine speed. The total amount of fuel used for a cold start is divided into the "amount for pilot injection" and the "amount for main injection". This takes place at engine speeds below 400 rpm and engine temperatures below 8°C.

Pilot injection is a series of injections in each cylinder prior to the main injection. If the temperature exceeds 8°C, the engine will be started with the "pilot injection amount" and the "main injection amount". Once the engine has started, i.e. when the engine speed exceeds 400 rpm, the fuel amount will be reduced gradually until a stable idling speed has been attained.

During normal running, the total amount of fuel is always one pilot injection and one main injection.

During normal running, the accelerator pedal potentiometer is one of the most important input signals to the engine control module for calculating the fuel amount together with the engine speed and engine temperature.