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Cylinder balancing

Cylinder balancing





The purpose of the cylinder balancing function is to balance the combustion pulses from each cylinder. At idle, this is done to compensate for different injected quantities in each cylinder and for differing degrees of efficiency in each cylinder. In other operating conditions, compensation is primarily made for differing degrees of efficiency in each cylinder. This is carried out by calculating and modifying the injected quantity for each cylinder individually.

The engine control module measures crankshaft speed after each power stroke. The next time the cylinder is set to ignite, a calculation is ready, the result of which constitutes a compensation quantity for the upcoming combustion. This compensation quantity is adjusted so that the upcoming combustion generates the same operating pulse after combustion as the other cylinders.

The average compensation quantity for the four cylinders is adjusted by 0% so that idling speed is not affected by the cylinder balancing function. The limit for the range of correction is 5 mg/combustion.

Cylinder balancing is not active


- under 200 rpm

- over 2000 rpm

- under 2 mg/combustion

- over 40 mg/combustion


The calculations are performed with the following variables


- Engine RPM

- Injected fuel quantity




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