Method for determining the fuel content of the regeneration gas in an internal combustion engine comprising direct fuel-injection with shift operation

An electronic control system configured to perform a method for determining a fuel content of a regeneration gas upon regeneration of an intermediate fuel vapor storage unit in an internal combustion engine, the method including the steps of:

• performing gasoline direct injection in lean mode;
• supplying stored fuel vapor to the internal combustion engine in the form of the regeneration gas via a controllable tank venting valve;
• determining the fuel content of the regeneration gas in accordance with a signal of an exhaust gas analyzer probe in an exhaust gas of the internal combustion engine;
• performing, with a closed tank venting valve, an adjustment between the signal of the exhaust gas analyzer probe and a preselected setpoint in which the exhaust gas analyzer probe signal is combined with a correction quantity while the tank venting valve is closed so that a result of the combination corresponds to the setpoint;
• combining, with an open tank venting valve, the exhaust gas analyzer probe signal with the correction quantity;
• and
• determining a regeneration gas charge from the result of the combination.