Patent ID: 7996144

Claim:
A method of controlling an internal combustion engine in an open-loop, wherein the internal combustion engine comprises a fuel metering system, a tank fill-level gauge for determining a tank content and a change in the tank content, a sensor for detection of a cylinder charge for determining an air mass supplied to the internal combustion engine, and at least one exhaust gas probe for determining and controlling in a closed-loop the oxygen content in the exhaust gas, the method comprising: determining an initial value of a air-fuel ratio from the air mass and the change measured in the tank content, wherein the oxygen content in the exhaust gas is further accounted for; ascertaining a second value for the air-fuel ratio from the air mass supplied to the internal combustion engine during an idle mode and the fuel amount supplied with the aid of the fuel metering system; and comparing the initial and the second value for a correlation within a specified limit, wherein the initial and the second value are checked for correlation with a lambda control factor and a mixture adaptation, and whereinupon deviation of the initial and the second value from each other an error in the fuel metering system is inferred, an error the determination of the air mass is inferred, an error with the tank fill-level gauge is inferred, and an error in the determination of the lambda control factor or with the mixture adaptation is inferred.