Abstract: A setting system (14) for setting the quantity of fuel delivered to an internal combustion engine has a first setting unit (10.1.1) and a second control unit (10.2.1). The first control unit emits, as a function of signals which are supplied to it from a first sensor arrangement (11.1), a first manipulated variable to the fuel injection pump (12.1). The second setting unit determines, as a function of signals from a second sensor arrangement (11.2), a second manipulated variable, which likewise would be directly suitable for actuating the fuel injection pump, but which is used to calibrate the first setting unit. The setting system thus set up is used whenever a sensor arrangement is used as second sensor arrangement which is slower, but measures more accurately than the first sensor arrangement. Then, the second manipulated variable corresponds more accurately to a value necessary for achieving a desired lambda value than the first manipulated variable.