Patent ID: 8126633

Claim:
A method for operating an internal combustion engine, with at least a first map of prefixed first values is predetermined, each prefixed first value being a function of a prefixed nominal fuel quantity (Q ecu — prefix ), the method comprising the steps of: determining a nominal fuel quantity (Q ecu ) for an injection (Q UEGO ); calculating an actual, torque forming, injected fuel quantity of said injection (Q UEGO ), wherein said actual, torque forming, injected fuel quanity (Q UEGO ) is calculated according to a following equations Q UEGO = A afm λ * fac where A afm is an air mass measured by an air mass sensor, λ is an air to fuel ratio and “fac” is a predetermined constant provided by the equation: fac = ( A F ) st ⁢ ρ where ρ is a fuel density and (A/F) st is a stoichiometric air to fuel ratio; calculating an at least one first parameter (Q delta ) which is related to the actual, torque forming, injected fuel quantity of said injection (Q UEGO ); modifying said nominal fuel quantity (Q ecu ) according to said at least one first parameter (Q delta ) so as to obtain a corrected fuel quantity (Q ecuCorr ) that corresponds to an actual fuel quantity injected during said injection (Q UEGO ); comparing said corrected fuel quantity (Q ecuCorr ) with each of said prefixed nominal fuel quantity (Q ecu — prefix ); operating the internal combustion engine using, from the first map, the first values which correspond to said corrected fuel quantity (Q ecuCorr ), according to a result of said comparing said corrected fuel quantity (Q ecuCorr ) with each of said prefixed nominal fuel quantity (Q ecu — prefix ).